KS-017SB Universal 5/8" (16mm) Stud 3/8" -16 Male and 1/4" -20 Male Threads

The universal adaptor spigot is a double-sided Baby 5/8" (16mm) stud with 1/4"-20 male thread on one side and a 3/8"-16 male thread on the other. The stud is round and will fit into any 5/8" (16mm) receiver.