SunwayFoto D-Ring T-Screw for Quick-Release Plates SunwayFoto 2x D-Ring T-Screw - SunwayFoto 6 Year Warranty Material: Stainless steel Mounting Thread: 1/4"-20 male screw Dimensions: Shaft Length: 0.37" (9.39mm)Total Length: 0.5" (12.7mm)Head Diameter: 0.87" (22.09mm)