Milwaukee® SHOCKWAVE™ Impact Duty™ locking bit holders are engineered to be the most durable, strongest locking tip holders on the market. The intuitive auto-locking design fits all inserts and 1/4 in. hex bits and the small-profile quick release collar allows for easy one-handed bit tip changes. The new locking bit holders feature two magnets to maximize magnetic transfer and holding power to the fastener and prevents drops. As with all SHOCKWAVE™ impact duty accessories, each bit holder features and optimized Shock Zone™ geometry to provide up to 30x longer life and absorb 3x more torque to prevent from breakage. Optimized Shockzone: Absorbs Peak Torque and Prevents BreakingAuto-Locking Design: Fit all Inserts and 1/4 in. Hex bitsQuick Release Collar: One Handed Bit ChangesDual Magnets: Maximize Magnetic Transfer and Holding Power to FastenerCustom alloy 76 steel maximizes resistance to wear and shock