1. This lens collar is tailor-made for Canon EF 70-200mm f/2.8L USM, Canon EF 70-200mm f/2.8L IS USM, Canon EF 70-200mm f/2.8L IS II USM, Canon EF 70-200mm f/2.8L IS III USM, Canon EF 100-400mm f/4.5-5.6L IS USM, Canon EF 35-350mm f/3.5-5.6L USM, Canon EF 300mm f/4L IS USM, can't be used for other lens. | 2. The net weight of the tripod mount ring is about 135g, inner diameter is about 78mm, the ring width is about 18mm; Bottom is added 65mm long quick release plate, with 1/4" and 3/8" screw holes; laser scanning technology is used to accurately obtain the lens parameters, and then the shape of the inner diameter of the lens support is accurately carved based on the data. | 3. The tripod mount ring is made of high-density Aviation Aluminum; precisely machined by world-class high-end CNC turning center and hollowed-out carved by diamond combined cutter heads; adopting vibration polishing technology, which improves grinding precision by 20% than manual; multiple anodized, which improves the fineness and uniformity of the color of the metal surface by 10%; the appearance and exquisite workmanship is much better than similar products made by mold. | 4. This lens support bottom is AS standard quick release plate, compatible with RRS / ARCA-SWISS / PMG / WIMBERLEY / MARKINS / PHOTOCLAM / SUNWAYFOTO / BENRO / SIRUI / MARSACE / ISHOOT tripod ball head of Arca 39mm fit, suitable for iShoot IS-JZ30 / IS-JZ50 / IS-JZ64 / IS-QJ58 / IS-QJ64-FD / IS-JZ60BK / IS-JZ70MFT / IS-JZ80BK clamp. | 5. Package Includes: 1 x iShoot Tripod Mount Ring IS-C720XB (The other items in the photos not listed here are for illustrating only, not included.)