Tripod Mount Ring Base Lens Collar Bracket Foot for Canon RF 400mm f/2.8L IS USM
RF 400mm F2.8L IS USM, RF 600mm F4L IS USM, RF 800mm F5.6L IS USM. Compatible with Canon EF 400mm F2.8L IS III USM, EF 600mm F4L IS III USM. Canon RF 400mm f/2.8L IS USM. Canon EF 400mm f/2.8L IS III USM.