Multi-purpose rail nodal slide with AS standard screw-knob clamp, precise laser engraved, Scale and spirit level, excellent for panoramic and macro photography. Clamp with captive knob stops at maximum opening. High quality aluminum alloy is used to ensure a light weight but super high strength support. All metal construction.double dovetail clamp plate(Upper and lower layer), can be The left Rotated 90° and The right Rotated 90°. 39 mm wide double dovetail clamp plate,Universal Quick Release System has been designed to be compatible with other brand quick release systems. Suitable for most ball heads. dovetail clamp plate with expandable 1/4 screw holes- 5pcs,You can install other equipment Compatible with AS standard plate such as: RRS, ARCA-SWISS / KIRK / Wimber ley / MARKINS / SUNWAYFOTO / Kangrinpoche / BENRO / SIRUI etc. Compatible with ballhead tripod or monopod of Gitzo, Manfrotto, RRS, Arca-Swiss