Bosch Expert SDS plus-7X, Rotary hammer, Hammer drill bit, 0.394" (1 cm), 8.46" (215 mm), Concrete, Stone, 5.91" (15 cm) Bosch Expert SDS plus-7X. Proper use: Rotary hammer, Drill bit type: Hammer drill bit, Drill bit diameter: 0.394" (1 cm). Number of drill bits: 50 pc(s)