Vise IT – Easy Slug w/ Slug IT & Slug IT Molly SetThe Vise IT system of Interchangeable Thumb Slug system has several pieces. This set includes 5 Vise Grip Urethane Thumb slugs with the Slug It attached. Ready to be drilled. After drilling your IT thumb hole, you will used the Slug IT Molly for that extra security. The Slug IT Molly is designed to reduce the stress on the Slug IT.