The Dormer Countersink drill bit is available with tri flat shank. A 90 degree countersink designed is used for chamfering standard fastener holes and removing burrs from drilled holes. Shank with three ground flats gives improved holding in three jaw chucks. Suitable to chamfer holes in many materials.
Bright due to uncoated Cylindrical shank with 3 flat High speed steel tool material Right hand rotation and cutting DIN 335 C Straight shank countersink standards