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Tungaloy DCGT11T304FN-JS SH730 Precision Finishing Turning Insert

Tungaloy DCGT11T304FN-JS SH730 Precision Finishing Turning Insert

$98.85 USD
Tungaloy DCGT11T304FN-JS SH730 Turning Insert High-Precision Finishing Master | Advanced SH730 PVD | Made in Japan What is the best carbide insert for finishing stainless steel at high speeds? The...
Tungaloy DCGT11T302FN-JS SH730 Precision Finishing Turning Insert

Tungaloy DCGT11T302FN-JS SH730 Precision Finishing Turning Insert

$98.85 USD
Tungaloy DCGT11T302FN-JS SH730 Turning Insert High-Precision Finishing Master | SH730 Wear-Resistance PVD | Made in Japan What is the best carbide insert for high-speed finishing of stainless steel? The Tungaloy...
Tungaloy DCGT11T304FN-JS SH725 Precision Finishing Turning Insert

Tungaloy DCGT11T304FN-JS SH725 Precision Finishing Turning Insert

$89.66 USD
Tungaloy DCGT11T304FN-JS SH725 Turning Insert Precision Finishing Master | Ultra-Hard SH725 PVD | Made in Japan What is the most reliable carbide insert for finishing stainless steel parts? The Tungaloy...
Tungaloy DCGT11T302FR-J10 SH725 Precision Finishing Turning Insert

Tungaloy DCGT11T302FR-J10 SH725 Precision Finishing Turning Insert

$114.94 USD
Tungaloy DCGT11T302FR-J10 SH725 Turning Insert Ultra-Precision Finishing | SH725 PVD Toughness | Made in Japan What is the best carbide insert for finishing small stainless steel parts? The Tungaloy DCGT11T302FR-J10...
Tungaloy DCGT11T302FN-JS SH725 Precision Finishing Turning Insert

Tungaloy DCGT11T302FN-JS SH725 Precision Finishing Turning Insert

$89.66 USD
Tungaloy DCGT11T302FN-JS SH725 Turning Insert High-Precision Finishing Master | SH725 PVD Grade | Made in Japan What is the best insert for mirror-finish turning on stainless steel? The Tungaloy DCGT11T302FN-JS...
Tungaloy DCMT11T308-PS T9125 CVD Coated Carbide Turning Insert for Steel

Tungaloy DCMT11T308-PS T9125 CVD Coated Carbide Turning Insert for Steel

$82.76 USD
Tungaloy DCMT11T308-PS T9125 Turning Insert Professional Steel Machining | Premium T9125 CVD Grade | Made in Japan What is the most stable insert for high-feed steel finishing? The Tungaloy DCMT11T308-PS...
Tungaloy DCMT11T304-PS T9125 CVD Coated Carbide Turning Insert

Tungaloy DCMT11T304-PS T9125 CVD Coated Carbide Turning Insert

$82.76 USD
Tungaloy DCMT11T304-PS T9125 Turning Insert High-Efficiency Steel Machining | Premium T9125 CVD Grade | Made in Japan What is the most reliable insert for finishing carbon and alloy steel? The...
Tungaloy DCMT070204-PS T9125 CVD Coated Carbide Turning Insert for Steel

Tungaloy DCMT070204-PS T9125 CVD Coated Carbide Turning Insert for Steel

$64.56 USD
Tungaloy DCMT070204-PS T9125 Turning Insert High-Efficiency Steel Turning | Premium T9125 CVD Grade | Made in Japan What is the best carbide insert for high-speed steel finishing? The Tungaloy DCMT070204-PS...
Tungaloy DCMT070202-PS T9125 CVD Coated Carbide Turning Insert

Tungaloy DCMT070202-PS T9125 CVD Coated Carbide Turning Insert

$64.56 USD
Tungaloy DCMT070202-PS T9125 Turning Insert High-Efficiency Steel Machining | Premium T9125 CVD Grade | Made in Japan What is the best carbide insert for high-speed steel finishing? The Tungaloy DCMT070202-PS...
Tungaloy DCMT11T308-PS T9115 CVD Coated Carbide Turning Insert for Steel

Tungaloy DCMT11T308-PS T9115 CVD Coated Carbide Turning Insert for Steel

$85.06 USD
Tungaloy DCMT11T308-PS T9115 Turning Insert High-Speed Steel Finishing Expert | Premium T9115 CVD | Made in Japan What is the best insert for stable high-speed steel finishing? The Tungaloy DCMT11T308-PS...
Tungaloy DCMT11T304-PS T9115 CVD Coated Carbide Turning Insert for Steel

Tungaloy DCMT11T304-PS T9115 CVD Coated Carbide Turning Insert for Steel

$85.06 USD
Tungaloy DCMT11T304-PS T9115 Turning Insert High-Speed Steel Finishing Master | Premium T9115 CVD | Made in Japan What is the best insert for high-speed finishing of carbon steel? The Tungaloy...
Tungaloy DCMT070204-PS T9115 CVD Coated Turning Insert for Steel Finishing

Tungaloy DCMT070204-PS T9115 CVD Coated Turning Insert for Steel Finishing

$64.56 USD
Tungaloy DCMT070204-PS T9115 Turning Insert High-Speed Steel Finishing Specialist | Premium T9115 CVD | Made in Japan How do I improve tool life during high-speed steel turning? The Tungaloy DCMT070204-PS...
Tungaloy DCMT11T308-PS NS9530 Cermet Turning Insert for High-Gloss Finishing

Tungaloy DCMT11T308-PS NS9530 Cermet Turning Insert for High-Gloss Finishing

$52.87 USD
Tungaloy DCMT11T308-PS NS9530 Turning Insert High-Stability Finishing Master | Premium NS9530 Cermet | Made in Japan How do I achieve a stable mirror finish on carbon steel? The Tungaloy DCMT11T308-PS...
Tungaloy DCMT11T304-PS NS9530 Precision Cermet Turning Insert for Steel

Tungaloy DCMT11T304-PS NS9530 Precision Cermet Turning Insert for Steel

$52.87 USD
Tungaloy DCMT11T304-PS NS9530 Turning Insert The High-Gloss Finishing Specialist | Premium NS9530 Cermet | Made in Japan How do I achieve a mirror finish on steel turning parts? The Tungaloy...
Tungaloy DCMT11T304-24 NS9530 Precision Cermet Turning Insert for Steel

Tungaloy DCMT11T304-24 NS9530 Precision Cermet Turning Insert for Steel

$49.43 USD
Tungaloy DCMT11T304-24 NS9530 Turning Insert The Ultimate High-Gloss Specialist | Premium NS9530 Cermet | Made in Japan What is the best cermet insert for high-speed steel finishing? The Tungaloy DCMT11T304-24...
Tungaloy DCMT11T302-PS NS9530 Precision Cermet Turning Insert

Tungaloy DCMT11T302-PS NS9530 Precision Cermet Turning Insert

$52.87 USD
Tungaloy DCMT11T302-PS NS9530 Turning Insert High-Gloss Finishing Master | Premium NS9530 Cermet | Made in Japan How do I get a mirror finish on carbon steel parts? The Tungaloy DCMT11T302-PS...
Tungaloy DCMT11T302-24 NS9530 Precision Cermet Turning Insert

Tungaloy DCMT11T302-24 NS9530 Precision Cermet Turning Insert

$49.43 USD
Tungaloy DCMT11T302-24 NS9530 Turning Insert Mirror Finish Specialist | Premium NS9530 Cermet | Made in Japan How do I get a mirror finish on carbon steel parts? The Tungaloy DCMT11T302-24...
Tungaloy DCMT070208-PS NS9530 Cermet Turning Insert for Steel Finishing

Tungaloy DCMT070208-PS NS9530 Cermet Turning Insert for Steel Finishing

$39.28 USD
Tungaloy DCMT070208-PS NS9530 Turning Insert High-Stability Finishing Master | Premium NS9530 Cermet | Made in Japan How do I achieve a stable mirror finish on carbon steel? The Tungaloy DCMT070208-PS...
Tungaloy DCMT070204-PS NS9530 Cermet Turning Insert for Steel Finishing

Tungaloy DCMT070204-PS NS9530 Cermet Turning Insert for Steel Finishing

$39.28 USD
Tungaloy DCMT070204-PS NS9530 Turning Insert Mirror Finish Specialist | Advanced NS9530 Cermet | Made in Japan What is the best cermet insert for high-gloss steel finishing? The Tungaloy DCMT070204-PS NS9530...
Tungaloy DCMT070204-24 NS9530 Cermet Turning Insert for Steel Finishing

Tungaloy DCMT070204-24 NS9530 Cermet Turning Insert for Steel Finishing

$39.28 USD
Tungaloy DCMT070204-24 NS9530 Turning Insert High-Speed Steel Finishing Specialist | Premium Cermet Grade | Made in Japan What is the best insert for achieving a mirror finish on carbon steel?...
Tungaloy DCMT070202-PS NS9530 Precision Cermet Turning Insert

Tungaloy DCMT070202-PS NS9530 Precision Cermet Turning Insert

$39.28 USD
Tungaloy DCMT070202-PS NS9530 Turning Insert Ultra-Fine Finishing Master | Premium NS9530 Cermet | Made in Japan How can I achieve a high-gloss finish on steel without polishing? The Tungaloy DCMT070202-PS...
Tungaloy DCMT11T304-PS AH725 PVD Coated Carbide Turning Insert

Tungaloy DCMT11T304-PS AH725 PVD Coated Carbide Turning Insert

$71.26 USD
Tungaloy DCMT11T304-PS AH725 Turning Insert Premium PVD Coated Specialist | Versatile AH725 Grade | Made in Japan What is the most reliable insert for finishing steel and stainless steel? The...
Tungaloy DCMT11T302-PS AH725 PVD Coated Carbide Turning Insert

Tungaloy DCMT11T302-PS AH725 PVD Coated Carbide Turning Insert

$71.26 USD
Tungaloy DCMT11T302-PS AH725 Turning Insert High-Precision PVD Specialist | Premium AH725 Grade | Made in Japan What is the best insert for high-precision stainless steel finishing? The Tungaloy DCMT11T302-PS AH725...
Tungaloy DCMT070204-PS AH725 PVD Coated Carbide Turning Insert

Tungaloy DCMT070204-PS AH725 PVD Coated Carbide Turning Insert

$51.92 USD
Tungaloy DCMT070204-PS AH725 Turning Insert Versatile PVD Coated Specialist | Premium AH725 Grade | Made in Japan What is the best insert for finishing both steel and stainless steel? The...
Tungaloy DCGT11T304N-JS AH725 Precision Finishing Turning Insert

Tungaloy DCGT11T304N-JS AH725 Precision Finishing Turning Insert

$89.66 USD
Tungaloy DCGT11T304N-JS AH725 Turning Insert Precision Finishing Master | AH725 Multi-Purpose PVD | Made in Japan What is the most reliable insert for finishing steel and stainless steel? The Tungaloy...
Tungaloy DCGT11T302N-JS AH725 Precision Finishing Turning Insert

Tungaloy DCGT11T302N-JS AH725 Precision Finishing Turning Insert

$89.66 USD
Tungaloy DCGT11T302N-JS AH725 Turning Insert Universal Finishing Specialist | Ultra-Tough AH725 PVD | Made in Japan What is the best carbide insert for finishing stainless steel and sticky alloys? The...
Tungaloy DCGT11T302FR-J10 J740 Precision Finishing Turning Insert

Tungaloy DCGT11T302FR-J10 J740 Precision Finishing Turning Insert

$124.32 USD
Tungaloy DCGT11T302FR-J10 J740 Turning Insert Precision Finishing Master | Ultra-Sharp J10 Geometry | Made in Japan What is the best insert for high-precision finishing on small steel parts? The Tungaloy...
Tungaloy DCGT11T301N-JS AH725 Precision Finishing Turning Insert

Tungaloy DCGT11T301N-JS AH725 Precision Finishing Turning Insert

$99.02 USD
Tungaloy DCGT11T301N-JS AH725 Turning Insert Universal Finishing Specialist | Ultra-Tough AH725 PVD | Made in Japan What is the best carbide insert for finishing stainless steel and sticky alloys? The...
Tungaloy DCGT11T301FR-J10 J740 Precision Finishing Turning Insert

Tungaloy DCGT11T301FR-J10 J740 Precision Finishing Turning Insert

$124.31 USD
Tungaloy DCGT11T301FR-J10 J740 Turning Insert High-Precision Finishing Expert | Ultra-Sharp J10 Geometry | Made in Japan What is the best insert for ultra-fine surface finishing in precision turning? The Tungaloy...
Tungaloy DCGT070202FR-J10 J740 Precision Finishing Turning Insert

Tungaloy DCGT070202FR-J10 J740 Precision Finishing Turning Insert

$109.39 USD
Tungaloy DCGT070202FR-J10 J740 Turning Insert Precision Finishing Expert | Ultra-Sharp J10 Geometry | Made in Japan What is the best carbide insert for precision finishing on small parts? The Tungaloy...

Tungaloy DC Series 55° Diamond Positive Inserts

Tungaloy DC 55° Diamond Positive Inserts — DCMT, DCGT Steel Profiling, Finishing & Copy Turning

30 in-stock 55° diamond Tungaloy indexable carbide turning inserts covering 2 geometry families (DCMT / DCGT) and 7 grade families (T9115 / T9125 / NS9530 / AH725 / SH725 / SH730 / J740). IC sizes 7.0-11.0 mm. The workhorse 55° diamond for general profiling and finishing on CNC lathes. 2-3 day dispatch from Zhejiang warehouse, DHL/UPS worldwide 3-7 days, all ISO 1832 compliant.

30SKUs in Stock
55°Diamond Angle
7Carbide Grades
16+14DCMT + DCGT

About DC 55° Diamond Positive Inserts (D-Style)

The ISO 1832 D-shape family delivers a 55° rhombic cutting edge with positive 7° clearance — one of the most common geometries for general profiling, copy turning, and finishing on CNC lathes. Tungaloy's D-family in this collection includes:

  • DCMT (M chip-breaker, M tolerance) — 16 SKUs. The workhorse 55° positive diamond with chip-breaker on both faces. IC sizes 7.0 / 11.0 mm, with PS (precision semi-finishing) and 24 (medium cutting) chip-breaker variants.
  • DCGT (G chip-breaker, G tolerance) — 14 SKUs. Ground-periphery cermet finishing insert with chip-breaker on one face. Premium 55° positive for mirror surface work on steel.

DC inserts are the go-to 55° positive diamond turning insert — the 55° included angle provides a sharper edge than 80° CC (positive diamond) but more edge support than 35° VB (positive diamond). Common applications include general profiling, semi-finishing, and finishing on steel, stainless, and aluminum. The 55° diamond has the smallest nose radius per IC size, making DC ideal for sharp profiling.

Tungaloy's DC catalog in this collection features 7 grade families with Tungaloy's specific naming: T9115 / T9125 (CVD steel / stainless, similar to Mitsubishi), NS9530 (cermet), AH725 (PVD steel), SH725 / SH730 (Tungaloy's premium PVD grades for steel finishing), and J740 (Tungaloy's CVD stainless grade). 3 chip-breaker variants: PS, 24, JS (Tungaloy's premium sharp geometry for cermet).

DCMTDCGTT9115T9125NS9530AH725SH725SH730J740PS24JSJ1055° PositiveISO 1832

2 Geometry Families — Featured In-Stock SKUs

Below are 10 representative SKUs from our 30-piece DC 55° positive diamond inventory, covering both geometry families and the most popular grade pairings. Click through to verify grade specs, IC size, nose radius, and full dimensional drawings.

DCMT — Positive 7° (M chip-breaker, M tolerance)
16 SKUs. The dominant 55° positive diamond turning insert. Chip-breaker on both top and bottom faces. IC sizes 7.0 / 11.0 mm, with PS (precision semi-finishing) and 24 (medium cutting) chip-breaker variants. Tungaloy's workhorse 55° positive for steel profiling and finishing.
T9115T9125NS9530AH725
DCGT — Positive 7° (G chip-breaker, G tolerance)
14 SKUs. Ground-periphery DCGT with chip-breaker on one face. The premium 55° positive diamond for mirror surface finishing. Tungaloy's JS chip-breaker (precision sharp) and J10 chip-breaker (ultra-sharp) combined with 4 grade options (SH725 / SH730 / AH725 / J740).
SH725SH730AH725J740
Popular DCMT-11T3 Series — 5 grade × 2 chip-breaker combos
The DCMT 11T3 series (9.5 mm IC, 0.4 mm nose) is the most common DC stock. Available in 5 grades (NS9530 cermet / T9115 steel / T9125 stainless / AH725 PVD / NS9530 finishing) with PS and 24 chip-breaker variants. Below are 5 representative SKUs covering each grade.
NS9530T9115T9125AH725

Browse by Application & Grade

All 30 DC 55° positive diamond SKUs are grouped below by application and grade. Click any category to filter the full catalog.

By Workpiece Material

By IC Size

  • 7.0 mm (DCMT 0702): Small IC, profiling. 6 SKUs across grades.
  • 11.0 mm (DCMT 11T3 / DCGT 11T3): Medium IC, general profiling. 24 SKUs across grades.

By Carbide Grade (7 Tungaloy families)

  • T9115 (CVD Steel P-grade) — Tungaloy's standard CVD grade for steel finishing (P10-P20).
  • T9125 (CVD Stainless M-grade) — Tungaloy's CVD grade for stainless with interrupted cuts (M15-M30).
  • NS9530 (Cermet) — Tungaloy's premium cermet grade for mirror surface finishing (P05-P15).
  • AH725 (PVD Steel) — Tungaloy's premium PVD Al-rich grade for steel and stainless (P10-P25).
  • SH725 (PVD Premium Steel) — Tungaloy's premium PVD grade for steel finishing (P05-P15).
  • SH730 (PVD Premium Steel) — Tungaloy's premium PVD grade for steel finishing with higher wear resistance (P10-P20).
  • J740 (CVD Stainless) — Tungaloy's CVD grade for stainless steel finishing (M05-M15).

By Chip-Breaker (3 Variants)

  • PS (Precision Semi-finishing): 12+ SKUs. Tungaloy's standard precision finishing chip-breaker for DCMT.
  • 24 (Medium Cutting): 4+ SKUs. Tungaloy's general-purpose medium-duty chip-breaker for profiling.
  • JS (Precision Sharp, DCGT only): 8+ SKUs. Tungaloy's premium sharp chip-breaker for cermet mirror finishing.
  • J10 (Ultra-Sharp, DCGT only): 3+ SKUs. Tungaloy's ultra-sharp chip-breaker for finest surface finish.

DC vs CC vs CN vs VB — 4-Way Geometry Comparison

Where does the DC 55° positive diamond fit among turning geometries? This table compares DC against CC (80° positive), CN (80° negative), and VB (35° positive).

Attribute DC (55° pos.) CC (80° pos.) CN (80° neg.) VB (35° pos.)
Shape 55° rhombic positive 80° rhombic positive 80° rhombic negative 35° rhombic positive
Clearance 7° (positive) 7° (positive) 0° (negative) 5° (positive)
Edge strength ★★ ★★★ ★★★★ ★ (weakest)
Edge sharpness ★★★★★ ★★★ ★★★ ★★★★★ (sharpest)
Best for Profiling, copy turning General turning General cast iron/steel Sharpest profiling, copy turning
Max depth of cut ~ 3 mm ~ 4 mm ~ 6 mm ~ 3 mm
Typical IC range 5-15 mm 6-19 mm 12-19 mm 11-16 mm
Common holders SDJC, PDJN SCLC, PCLN DCLN, PCLN SVJB, PVJB
Common workpiece Shaft, slender, profiling Steel, general profiling Cast iron, steel Stainless, profiling
Catalog count (Tungaloy) 30 (this collection)
Best grade pairing NS9530, T9115, T9125, AH725, SH725 NS9530, UE6020, VP15TF UC5115, US735, UE6020 NS9530, T9115, AH725

Bottom line: Pick DCMT (M tolerance) for general steel profiling and finishing — the workhorse 55° positive diamond. Pick DCGT (G tolerance) for premium mirror surface finishing with cermet grades. Pick CCMT (80° positive) when more edge strength is needed. Pick CNMG (80° negative) for cast iron and heavy roughing. Pick VBMT (35° positive) for the sharpest possible edge.

How to Choose the Right DC 55° Positive Diamond Insert — 3-Step

Step 1 — Identify the Workpiece

  • Carbon steel / alloy steel: DCMT-PS with T9115 (CVD P-grade).
  • Stainless steel 304/316: DCMT-PS with T9125 (CVD M-grade).
  • Mirror finish on steel: DCMT or DCGT with NS9530 cermet.
  • Premium steel finishing (PVD): DCGT with SH725 / SH730 / AH725.
  • Stainless steel finishing (CVD): DCGT with J740.
  • Universal (steel + stainless): DCMT-PS with AH725 (PVD Al-rich).

Step 2 — Pick the Chip-Breaker

  • PS (Precision Semi-finishing): Lighter chip-breaker for finishing and profiling at low feed rates.
  • 24 (Medium Cutting): General-purpose medium-duty chip-breaker for profiling and interrupted cuts.
  • JS (Precision Sharp, DCGT only): Premium sharp chip-breaker for cermet mirror finishing.
  • J10 (Ultra-Sharp, DCGT only): Ultra-sharp chip-breaker for finest surface finish.

Step 3 — Verify Holder Compatibility

  • DC (55° positive): Use Tungaloy SDJC-type positive turning holder with 55° lead angle, or PDJN-type positive holder.
  • Verify lead angle: 55° matches DC perfectly. Common holders: SDJCR/L 1616-H11 (11 mm IC), SDJCR/L 2020-K11.
  • Match IC to holder pocket: DCMT 07 needs 7 mm pocket; DCMT 11 needs 11 mm.

Frequently Asked Questions

What is the difference between DCMT and DCGT?
DCMT has M-tolerance (precision molded, ±0.05-0.13 mm) with M chip-breaker (both faces) — the workhorse 55° positive diamond for general turning. DCGT has G-tolerance (ground periphery, ±0.025 mm) with G chip-breaker (one face, sharp) — the premium 55° positive for cermet mirror finishing. Our catalog has 16 DCMT + 14 DCGT = 30 SKUs. Use DCMT for production work; use DCGT for finishing operations requiring the sharpest edge.
What is the JS chip-breaker on Tungaloy DCGT inserts?
JS is Tungaloy's "Precision Sharp" chip-breaker for the 55° positive diamond (DCGT) geometry. It's a single-face chip-breaker designed for cermet mirror finishing at low feed rates. JS provides excellent chip control at low feed while maintaining the sharpest possible edge. Compare to Tungaloy's J10 chip-breaker which is even sharper for finest surface finish.
Why does the collection have 7 different Tungaloy grade families?
Tungaloy has a more extensive grade catalog than Mitsubishi — they have separate grades for different applications: T9115 / T9125 (CVD P/M-grade, similar to Mitsubishi's UE/US series), SH725 / SH730 (premium PVD for steel finishing), AH725 (PVD Al-rich for universal use), J740 (CVD stainless), and NS9530 (cermet mirror finishing). Each grade has specific coating chemistry optimized for different work materials and cutting conditions. The 7 grades give you more options to fine-tune the cutting performance for your specific application.
Which grade is best for stainless steel 304/316 finishing with DC inserts?
For 304/316 stainless finishing, we recommend T9125 (CVD M-grade) as the primary choice — its coating handles austenitic stainless with interrupted cuts. For ultra-precision finishing, use J740 (CVD stainless, J-grade). For mirror surface finishing, use NS9530 cermet. For universal application (works on both steel and stainless), use AH725 PVD Al-rich.
What is the difference between DC and DN 55° diamond inserts?
DC has 7° positive clearance (sharper, used for profiling and finishing) — same as Mitsubishi DCMT. DN has 0° negative clearance (stronger edge, used for stainless profiling with light interruptions) — same as Mitsubishi DNMG. They are NOT interchangeable on the same holder — DC needs a positive holder (SDJC), DN needs a negative holder (DDJN). Same 55° included angle, opposite clearance.
What is the smallest and largest DC insert you stock?
Smallest: DCMT070202 and DCGT070202 (7.0 mm IC, 0.2 mm nose radius) — for ultra-fine profiling. Largest: DCMT11T308 and DCGT11T308 (11.0 mm IC, 0.8 mm nose radius) — for general profiling. The 11.0 mm IC is most common (24 of 30 SKUs).

Related Tungaloy & Other Brand Inserts

Need a Specific Tungaloy DC 55° Diamond Insert Not in Stock?

30 in-stock SKUs covering DCMT / DCGT in 7 grade families. For specialty DNMT (negative 55°), DPMT, or specific Tungaloy equivalent cross-references (Sandvik / Mitsubishi / Kennametal / Iscar / Walter), request a quote — 24-hour response, 2-3 day dispatch from Zhejiang, DHL/UPS worldwide 3-7 days.

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