Shockwave™ impact-duty magnetic bit holders are engineered for extreme durability and up to 10X life. Made from proprietary steel and heat-treated to control hardness, the Shockwave™ impact-duty magnetic bit holders feature a powerful magnet allowing for a secure grip and unyielding bit engagement. The two-piece construction of the holders is the optimal assembly for abusive applications. Now use with Milwaukee® Shockwave™ Impact-duty Insert Magnetic Nut drivers.