Lisle 19250 6pc Stuck Bolt, Nut and Stud Remover. Removes Stuck Studs, Rounded Bolts & Nuts. The 6 piece set removes standard and metric bolts, nuts and studs from 1/4" to 9/16" (6mm to 14mm). Drive the proper size remover over the bolt head, nut or stud. The remover spine cuts into the bolt head or threads for a sure grip. Then use a back and forth motion with a wrench or socket to free the fastener. Works well even on flush mounted bolts and nuts. Provides a no slip grip that withstands high torque. Made of super strong, hardened tool steel for durability.