Features: Safe Screw installed to prevent drop of camera by accident You can change the location of the screw to fit different cameras For: Benro， Arca Swiss standard ballheads and other compatible accessories Material: aluminium alloy， stainless steel(screws) Screw: 1/4" Size: Approx. 50mm x 38mm x 10mm/1.97" x 1.50" x 0.39"Package included: 1x PU-50 Quick Release Plate