iShoot Lens Collar Tripod Mount Ring IS-C720XXB Compatible with Canon EF 400mm f/5.6L USM, EF 80-200mm f/2.8L, EF 70-200mm f/4L USM, EF 70-200mm f/4L IS USM, EF 70-200mm f/4L IS II USM; Bottom is 39mm ARCA Fit Quick Release Plate Feature, Compatible with Tripod Head & Clamp of RRS / ARCA-SWISS Fit; 2. Referring to and modified from original standard design, bearing is enhanced, details are improved, and added the features of quick release plate, more practical; 3. High temperature die casting molding of Aluminum alloy, CNC secondary processing, surface car paint, built-in flocking, copper knob, stainless steel anti-skid nails; 4. Weight is about 135g, inner diameter is about 65.5mm, width is about 18mm; split-structure, bottom with quick-release plate design, the plate’s length is about 60mm, with 1/4" and 3/8" screw holes; 5. Package Includes: 1 x iShoot Tripod Mount Ring IS-C720XXB (Note: The other items in the photos not listed here are for illustrating only, not included)