Quik Drive auto-feed screw driving systems are easy to use, durable and designed for a wide variety of fastening applications. Featuring quick-loading screw strips, precise countersink adjustment and a patented auto-advance mechanism, Quik Drive tools save time and expense on jobsites every day. Keep your Quik Drive systems in perfect condition with Simpson Strong-Tie® replacement parts. Quik Drive® 7-1/2 in. Mandrel (Pack of 12).