Bosch 1612026037 Selector Knob Assembly Selector Knob Assembly for Bosch Rotary Hammers 11224VSR,11228VSR,11224VSRC Selector Knob Assembly for Bosch Rotary Hammers 11226VS,11236VS,11253VSR and 11255VSR Genuine OEM replacement part. Also Available 1610905025 Ball Bearing for 11236VS,11224VSR,11228VSR,11226VS, 11255VSR,11253VSR Also 1617000262 Serv Pk (11236VS),1617000163 Bit Ret Asm (11224VSR),1615430001 Grease (11253VSR)