1. The lens tripod mount ring replacement foot is referencing to and modified from original factory design, nd the size is same as the original one; details are improved; bottom added the feature of Arca-Swiss fit quick release plate, more practical; | 2. The lens replacement foot is Only compatible with Nikon Nikkor AF-S 500mm f/5.6E PF ED VR and Nikkor AF-S 70-200mm f/2.8E FL ED VR lens; NOT compatible with Nikkor Z 70-200mm f/2.8 VR S, Nikkor AF-S 70-200mm f/2.8G ED VR, Nikkor AF-S 70-200mm f/2.8G ED VR II, and other 70-200/2.8 lenses; | 3. The lens collar replacement base is made of aviation aluminum, CNC precisely machined, anodized surface, with spring clip, knob lock and stainless-steel anti-skid nails; | 4. Bottom is Arca-Swiss fit quick release plate, compatible with RRS / ARCA-SWISS Fit Tripod Head & Clamp, and the length of the plate is about 70mm, reserved with 1/4 and 3/8 screw holes; the stainless-steel limit screws at the bottom are removable; | 5. The lens collar foot IS-THN720II can be combined with clamp mount converter IS-3950PRO (Sold Separately), which can be used for fluid heads with Manfrotto 50 structure; or combined with iShoot long focus lens support IS-TB02 (Sold Separately), for protecting the lens bayonet.