Milwaukee® SHOCKWAVE™ Impact Duty™ insert magnetic nut drivers are engineered for extreme durability and up to 30X life. Made from proprietary steel and heat treated to control hardness, the SHOCKWAVE™ Impact Duty™ magnetic nut drivers feature a powerful magnet allowing for a secure grip and unyielding bit engagement. The bits feature color-coded rings for quick and easy size identification. Designed for use with Milwaukee® SHOCKWAVE™ magnetic bit tip holders 2.36 in, 3 in, 6 in, 12 in, 30 deg Knuckle™ Pivoting Bit Holder and all bit tip holders.