Irwin Industrial 3094101 Fractional Fine NF Deep Well TheadChaser Set, 5-Piece Cleans and repairs threads without damaging the stud or fastener Deep Well Design - ThreadChaser repairs threads in recessed areas, including axle studs Low-Profile Hexagonal Head - Drive it with a socket, wrench, or pliersIncludes: 3/8-24NF, 7/16-20NF, 1/2-20NF, 9/16-18NF, 5/8-18NF Deep Well ThreadChaser