Neewer Black Metal PU-50 Universal Quick Release Plate Fits Arca-Swiss Standard for Tripod Ballhead (PU50 III) Superior quality aluminum alloy is used to ensure a light weight but super high strength support. Advanced CNC (Computerized Numeric Control) machine systems provide precise dimension to fit perfectly. Aluminum Anodized surface treatment assures years of corrosion and abrasion-resistant operaton. Anti-twist locking screws match the international standards Special anti-slip rubber pads enhance the grip between each plate and the mounted gear, and protect the gear from any damage due to mounting.