This is a universal adapter spigot stud for the studio usage. New version precision made 1/4"-20 to 3/8"-16 stainless steel (metal) screws. Two pieces packed, easy to use.
The double head stud is equipped with one 1/4'' screw on the one end and one 3/8'' screw on the other end. It is suitable for different kinds gears with 1/4'' and 3/8'' threaded holes. Small as it is, it is really useful! Wonderful!