This Clamp-On Ring from SmallRig is a step-up ring that allows you to mount the SmallRig 2660 matte box onto your lens with a 95mm outer diameter. The durable, lightweight plastic adapter fits the 114mm matte box opening and allows you to mount your matte box closer to the front of your lens, reducing the possibility of vignetting with wide lenses. It quickly clamps onto the matte box using its split-ring design that prevents twisting and movement.