SNAPPY 4-Piece Countersinking Drill Set Fits Festool Centrotec Chucks 3/32", 7/64" and 1/8" pilot with 3/8" counterbore; 9/64" pilot with 1/2" counterbore Each countersink tool includes replaceable HSS twist drill for drilling pilot hole Includes precision milled 3" long driver bit with hardened #2 Square Drive Insert Engages Centrotec chuck for extremely close axial alignment of bit and output shaft of drill Reduced run-out and maximum torque transfer between drill and bit