Key Features:1.It comes with a 15mm rail clamp and a slot for 1/4’’ screws.2.It is compatible with 15mm rod, which is tightened via a wingnut.3.It could attach the top handle with 1/4’’ threaded holes. SmallRig Single 15mm Rail Clamp 1549 could attach 15mm rod, which is tightened via a wingnut. It could attach the top handle with 1/4’’ threaded holes.Compatibility: Universal Package Includes: 1 x 15mm Rail ClampProduct Dimensions: 57x15x33mm Net Weight: 50gPackage Size: 110x130x40mmMaterial(s): Aluminum Alloy