All of the shanks are 3.2mm(1/8inch) and compatible with other multi-tool machines including . These 6PC HSS rotary burrs are perfect for all sorts off jobs like Model making and the like. Using an engraving machine or mini-Drill forms of cutting part provide efficient processing which materials length is about 40mm. For processing of metallic and Non-metallic surfaces. Great for craft, modelling, home, repairs etc you . Shank Diameter mandrels: 3.17mm(1/8inch). single one Length: 40mm. colour: Silver Material: High speed steel Package Contents: 6 x HSS rotary burr Only the above package content, other products are not included. Note: Light 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.