The 6 piece set removes standard and metric bolts, nuts and studs from 1/4" to 9/16" (6mm t 14mm). Provides a no slip grip that withstands high torque. Made of super strong, hardened tool steel for durability Drive the proper size remover over the bolt head, nut or stud. The remover spine cuts into the bolt head or threads for 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. Includes: . 19250 Stuck bolt, nut, and stud remover set. 19260 #1 remover. Fits 1/4" and 6mm. 19270 #2 remover. Fits 5/16" and 8mm. 19280 #3 remover. Fits 3/8" and 10mm. 19290 #4 remover. Fits 7/16" and 11mm. 19300 #5 remover. Fits 1/2" and 13mm. 19310 #6 remover. Fits 9/16" and 14mm