Hex drivers feature a 3 mm shaft and like VetKISS™ screws couple with the finger converting the screwdriver into a hex driver for screw removal. Alternatively, if a screw shaft breaks off prematurely, the hex driver and finger driver can be used to complete screw insertion or alternatively screw removal and replacement. Included in VetKISS™ implant starter sets. 1.8 mm hex driver: 1.0 mm screws. 2.5 mm hex driver: 1.4 mm and 1.6 mm screws. Stainless Steel.