For cutting or engraving or carving or grooving or slotting or drilling or hollowing or positioning or roughing or milling in materials like MDF,PVC,Acrylic,wood,solid wood,chipboard,composite board,organic board,core board,density board etc. these bits own sharp edge which is able for fast engraving that makes high efficiency durable,high precision and not easy to break it is smokeless and burr-free while processing the design of 2 flutes,mirror polishing,large chip space of CNC Router Bit makes non-stick c bs,smooth cutting and fast chip-removal size:about 3.175x17x38.5mm Material:Metal colour:Silver Package Contents: 10 x Double edged milling cutter Only the above package content, other products are not included. Note: Light shooting and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is 1-3cm.