ZRAMO TH257 1/4 Inch D Shaft D-ring Screw Adapter Threaded Screw Converter Adapter for Camera Tripod Qr Quick Release Plate MeFOTO tripod Adapter(Pack of 4) 4 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