Foto&Tech D Shaft D Shaped Ring Screw Adapter 1/4 Inch Thread for Camera Tripod Quick Release Plate Canon/Nikon/Sony/Pentax/Sigma/Olympus/Panasonic DSLR/SLR Camera Precision made  inch thread Stainless Steel 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. Approximate head diameter (including D-Ring ): 16.2mm Great replacement for the screw that fell out of my camera tripod.