TAP 5/16-18 H3 4FL,Plug Chamfer, Hand Pl-STI 783, TT78322(Pack of 1)783, Measurement System: Imperial, 5/16-18 Thread, UNC Thread Standard, 1-1/8 in Thread Length, 2-23/32 in Overall Length, 4 Flutes, Plug Chamfer, 0.318 in Shank Diameter, 0.238 in Square, HSS, Uncoated