The 85mm GEM-COAR85 Clamp-On Adapter Lens Adapter Ring for Select Matte Box from Genustech is a split-ring-design, Delrin adapter ring that enables you to mount the GML Lite, GWMC Wide Angle, and GPVCMC Panavision Wide Clip-On Matte Boxes onto a lens with an 85mm front. It clamps onto the outside of the lens and avoids needing to be screwed into the lens filter threads.
It is advisable to use clip-on matte boxes with lenses that do not have rotating fronts, as rotating fronts may lead to exposure changes when using a polarizer, or vignetting of your image as you matte box rotates.
Made from black Delrin to minimize reflections
The split ring design makes it easier to mount the adapter on your lens