Milwaukee SHOCKWAVEโข Impact Duty Locking Bit Holders feature two magnets to maximize magnetic transfer and holding power to the fastener and prevent drops. Plus, its optimized SHOCK ZONE geometry provides up to 30X longer life and absorbs 3X more torque to prevent breakage. The intuitive auto-locking design fits all inserts and 1/4″ hex bits and the small-profile quick release collar allows for easy one-handed bit tip changes.