A super clamp is a useful and versatile tool with 1/4"-20 and 3/8"-16 thread holes used to mount and connect various accessories as you need them be. It can be mounted on lights, cameras, umbrellas, shelves, tables, cross bars or on other super clamps. With non-slip rubber, this clamp holds your unit(s) securely without making any scratches. The jaw opens from 15mm (minimum) to 58mm (maximum).