SUNWAYFOTO® brand Arca-Swiss compatible PN-D3 for Nikon D3 camera. Precisely engineered / exact Arca Standard: 39mm dovetail. Precision CNC machined from solid aircraft-grade aluminum. Mounting screw: 1/4-20″ . Dovetail Width: 39mm. Upper Width: 70mm . Thickness 15mm. Weight: 51g . Length 79mm. All metal construction Includes allen wrench