YC604 Heavy-Duty Number Steel Stamps
Designed for heavy-strike operations, hard-metal marking and high-volume production, delivering clear, right-reading letter impressions. It shares YC601's character heights but adds a larger, thicker shank that takes heavier blows.
Suitable materials: Carbon steel, stainless steel, alloy steel and other hard metals that need more striking force — as well as forging and casting molds.
Core Features
Made of CR-V (6150) chrome-vanadium steel.
The character head reaches HRC 58–62 for lasting, clear marks; the striking end is tempered to HRC 38–46 to absorb impact and prevent cracking.
A larger shank and thicker cross-section spread the hammer force, resisting mushrooming and cracking under heavy strikes and long production runs. Each character height comes in several shank grades (H/L/R) to match striking force.
A double-bevel design makes visual alignment and precise striking easy.
Font and size are marked on the side of the stamp for fast identification during work.
The surface is sandblasted for a better anti-slip grip and greater durability.
Exclusive Patent · Multi-Function Storage Box
More than storage — a core accessory that boosts working efficiency and safety:
Patented in Taiwan, USA, France, Germany, China, Vietnam and more — an original design.
Strike with the stamp held in the box — your hands stay clear of the hammer for a safer, steadier hit.
The box keeps the tool perfectly flush with the workpiece — a straight strike and consistent depth, every time.
A built-in viewing window makes positioning easy and keeps impressions from skewing.
Rotate the box freely to suit the way you work.
Patented PP box with a three-hole lid for fast, safe daily access.

Dimensions (character height C)
| Item No. | Character face C | Shank · square A | Shank length ±0.4 B |
|---|---|---|---|
| YC604L-1.5 | 1.5mm (1/16") | 7.93mm | 71mm |
| YC604H-2.5 | 2.5mm (3/32") | 7.93mm | 64mm |
| YC604L-2.5 | 2.5mm (3/32") | 7.93mm | 70mm |
| YC604H-3 | 3.0mm (1/8") | 7.93mm | 64mm |
| YC604L-3 | 3.0mm (1/8") | 9.52mm | 70mm |
| YC604R-3 | 3.0mm (1/8") | 12.70mm | 79mm |
| YC604L-4 | 4.0mm (5/32") | 9.52mm | 70mm |
| YC604H-5 | 5.0mm (3/16") | 9.52mm | 68mm |
| YC604L-5 | 5.0mm (3/16") | 11.11mm | 70mm |
| YC604H-6 | 6.0mm (1/4") | 11.11mm | 76mm |
| YC604L-6 | 6.0mm (1/4") | 12.70mm | 76mm |
| YC604R-6 | 6.0mm (1/4") | 15.85mm | 89mm |
| YC604H-10 | 10.0mm (3/8") | 14.28mm | 81mm |
| YC604L-10 | 10.0mm (3/8") | 15.85mm | 86mm |
*H/L/R are different shank grades at the same character height — choose by striking force.

→ For material, hardness, usage and other common questions, see the Steel Stamp FAQ
