Feature: 1. Aluminum Alloy Material: This product is made of aluminum alloy material, which is durable and not easily damaged, and can be used by users for a long time. 2. CNC Processing: The ring is processed using CNC technology, which reduces weight through hollowing, polishing, and anodizing the surface to make the product performance more stable. It is equipped with stainless steel screws. 3. Product Function: Fix the lens on a tripod, which can easily rotate in all directions to meet photography needs. There is flocking on the inside to prevent scratching the surface of the camera lens. 4. Quick Installation Board: The product adopts a 2 stage design with a 180 degree quick lock knob; The inner diameter of the product is about 80mm/3.15in, the width is about 18mm/0.71in, and the length of the quick assembly plate is about 90mm/3.54in; It is suitable for Tamron 100-400mm f4.5-6.3 Di VC USD (A035) lenses. 5. Strong Compatibility: The quick installation board adopts for AS standard, compatible for RRS, for ARCA, for SWISS, for PMG, for WIMBERLEY, for MARKINS, for SUNWAYFOTO, for BENRO, for SIRUI, for MARACE, for ISHOOT and other standard PTZ, suitable for IS JZ30, IS JZ50, IS JZ64, IS QJ58, IS QJ64, IS QJ64 FD, IS JZ60BK, IS JZ70MFT, IS JZ80BK, etc. Specification: Item Type: Tripod collar mount ring Weight: 191.00g/6.73oz Material: Aluminum alloy Ring Inner Diameter: Approximately 80mm/3.15in Ring Width: 18mm/0.71in Applicable Lens: For Tamron 100 to 400mm lens Threaded Hole: G1/4, G3/8. Package List: 1 x Tripod Collar Mount Ring