Features: Lens collar support is custom-made according to the shape and structure of the lens and is only for RF 100-400mm f/5.6-8 IS USM lens. Made of aviation aluminum, CNC precision machining, hollow weight reduction design, polishing and surface anodizing treatment, beautiful appearance and fine workmanship. The inner wall of the tripod ring with irregular irregular structure has reserved switch holes, which does not affect the use of the switch on the lens, it cannot be rotated, and only supports horizontal shooting, not vertical shooting. A 50mm long Arca standard quick release plate is added to the bottom of the tripod ring, which can be directly matched with a 39mm Arca-swiss tripod ball for head, panoramic gimbal, clip, etc. 1/4" and 3/8" screw holes and stainless steel anti-slip screws are also reserved. , you can attach the lens directly to the tripod. The dovetail slot at the bottom of the lens mount is 39mm Arca-Swiss standard, for ISHOOT/RRS/ARCA-SWISS / tripod for head for Arca 39mm, suitable for iShoot IS-JZ50/ IS-JZ64/IS-QJ58/IS-JZ60BK/IS-JZ70MFT/IS-JZ80BK etc. Specifications: Material: Aluminum Alloy Colour: Black Lens Inner Diameter: Approx. 76mm/2.99" Width: Approx. 22mm/0.87" Length of Plate: Approx. 50mm/1.97", with 1/4" and 3/8" screw holes Applicable Model: for RF 100-500mm F4.5-7.1L IS USM Lens Package Includes: 1x Tripod Mount Ring IS-RF140 note: Contact surface between the inner wall of the tripod ring and the lens is made of plastic composite film, and the lens surface will not be worn after being installed correctly; there should be no stickers on the lens surface installation position. Please allow 0-1cm error due to manual measurement. pls make sure you do not mind before you order. Due to the difference between different monitors, the picture may not reflect the actual color of the item.