This 20 pcs electric polishing are for DIY polished engraving, cutting, polishing (wood, polishing purposes). These are all high speed steel tools with 3mm shank.

Features:
Apply high speed steel, high hardness, wear-resistant & .
Suit to engrave, polish, slot materials like wood, .
High working efficiency, grinding effect.
20 different tools, include: rotary burrs, grinding head and rotary burr cutting tools etc.
Suits most kinds of rotary tools, electric grinder and .
Perfect to use for wood, , other not hard materials.

Specifications:
Material: High Speed Steel
Shank Diameter: 3mm / 0.118in
Total Length: 40mm / 1.57in 
Package Size: 7.5 * 6.5 * 0.5cm / 2.95 * 2.56 * 0.19in
Package Weight: 57g / 2.01oz

Note:
For better function and tool conservation, this set is not suitable for engraving hard wood, metal or stone.
It is suitable for wood, and materials doesn't have so high hardness.

Package List: E2114
20 * High Speed Steel Rotary Burs