Extractor sockets are precision engineered to easily extract damaged, stripped, rusted or frozen bolts and nuts The internal thread design provides excellent gripping power, the more torque you apply the tighter the sockets grip Set Includes: 3/4" (19mm), 11/16", 17mm, 5/8" (16mm), 9/16" (14mm), 13mm, 1/2", 12mm, 7/16" (11mm), 10mm, 3/8", 5/16" (8mm), 1/4" .