Foto4easy QB-4W Quick Release QR Plate for SONY VCT-D580RM/ VCT-D680RM/ VCT-R640/ Velbon CX-888/CX-444/CX-460 A QR plate can be kept attached to the camera's base and allows the user to quickly and easily attach or remove the camera from the tripod without having to waste time fumbling with the threaded mount. Spare QR plate Suitable for Velbon CX-444, CX-888, CX-460, CX-460mini, CX-470, CX-570, CX-690, DF-50 SONY VCT-D580RM, VCT-D680RM, VCT-R640 Bottom Size: 44mm(1.73") x 44mm(1.73") Weight: 31g/1.09oz 1/4 inch tripod socket