Industrial Tools Quick Change Magnetic Bit Holder Extensions, 6-4-3 Inch, 2 Pack Must-have accessory set for power drills and impact drivers Extensions in lengths 6", 4" & 3" for superior access for hard-to-reach fasteners Strong permanent magnets hold bits securely in place; accepts all 1/4" hex-shank bits 1/4" quick-change hex shanks fit all power drills, 1/4" impact drivers and hand-held drivers Hardened tempered tool steel with chrome-finish holders manufacturer's (2-Pack)