The DEWALT Impact Ready 3 in. Lock Mag Extension provides users exactly what they need when fastening or drilling with hex-shank accessories. The locking mechanism securely keeps the accessory in place during use and the quick-change features makes it easy to change accessories on the job. The lock mag extension's robust magnetism provides optimal fastener retention for screwdriving applications. The accessory locking extension's durable, uniquely designed locking mechanism allows users to not only drive with screwdriving bits, but accept all hex-shank accessories; making these holders accept bits and longer, as well as hex-shank drill bits. The slim profile allows users to complete more applications than bulkier, competitive designs like countersinking screws in brackets or when installing fasteners in close quarters.