Main Features: 1. Made of Aviation Aluminum, CNC precisely machined, surface anodic oxidation, with stainless steel screw, lightweight design of hollow, weight is about 140g; 2. Referring to and modified from Nikon original standard design, bearing is enhanced, details are improved, and bottom added the feature of quick release plate, more practical; suitable for Nikon AF 80-400mm f/4.5-5.6D ED VR and Nikon AF-S 300mm f/4D IF-ED lenses; 3. Tripod ring diameter is about 77mm, and width is about 16mm, the use of embedded PP material to increase the damping and reduce the lens wear; accurate bayonet, same to the original one, easy to quickly disassemble and adjust the body composition; tripod ring comes with quick-release plate about 65mm long, bottom with 1/4" screw hole; 4. Quick release plate is AS 39mm standard, compatible with RRS / ARCA-SWISS / KIRK / WIMBERLEY / MARKINS / SUNWAYFOTO / KANGRINPOCHE / BENRO / SIRUI / MARSACE / ISHOOT ball head of Arca 39mm fit, suitable for IS-JZ30 / IS-JZ50 / IS- JZ64 / IS-QJ58 / IS-QJ64 / IS-JZ60BK / IS-JZ70MFT / IS-JZ80BK. Package Includes: 1 x iShoot All-metal Lens Tripod Mount Ring IS-N840D (Note: The other items in the photos not listed here are for illustrating only, not included)