TILTA Seamless Focus Gear Ring 75-77mm, set of 2. Unused, new condition. These gear rings are for using still lenses with cinema-style follow focus systems. Compatible lenses are as follows (information from B&H Photo Video): Sony FE 70-200mm f/4 G OSS Sony FE 16-35mm f/4 ZA Sony FE 24mm f/1.4 GM Canon EF 70-300mm f/4-5.6 IS II USM Canon EF 24-70mm f/2.8L II USM Canon EF 24-105mm f/4L IS USM Canon EF 24-105mm f/4 IS II USM Canon EF 24-70mm f/2.8L II USM Canon EF 24-105mm f/4L IS USM Canon RF 24-105mm f/4.1-7.1 IS STM Canon EF 24-105mm f/4 IS II USM Canon EF-S 18-135mm f/3.5-5.6 IS STM Canon EF-S 18-200mm f/3.5-5.6 IS Canon EF-S 15-85mm f/3.5-5.6 IS USM Canon EF 100mm f/2 USM FUJIFILM XF 16-55mm f/2.8 R LM WR FUJIFILM XF 90mm f/2.0 R LM WR Panasonic Leica DG Vario-Elmarit 50-200mm f/2.8-4 ASPH POWER OIS Panasonic Lumix S 20-60mm f3.5-5.6 - Brand: TILTA - Model Name: Seamless Focus Gear Ring - Size: 75-77mm - Quantity: Set of 2