The 77mm Offset Step-up Ring with 100mm Outside Diameter from Cavision is an AR series offset adapter ring. The ring screws onto the front of a lens with 77mm filter thread and provides a 100mm O.D. surface for mounting a clamp-on matte box. The offset adapter ring is useful for clamping on a matte box when the matte box needs to be pushed back slightly further on the lens, to avoid vignetting.
- 77mm rear thread (male)
- 100mm outside diameter