SmallRig D Shaft D-ring 1/4 Inch Thead Camera Screw for DSLR Camera Rig - 838 2 PACK Precision made 1/4"-20 thread Stainless Steel (metal) Tripod screws. Total length including base: 14.5mm. Total shaft length: 10.5mm. Threaded part of the shaft: 6mm,No thread part of shaft: 4.5mm. approx.Head diameter(including D-Ring ): 16.2mm