The 100mm LanParte ARRI LMB Lens Clamp Adapter is compatible with the ARRI LMB-5, LMB-15, LMB-25, and LMB-4x5 matte boxes. It's an aluminum adapter designed specifically for lenses with a 100mm front lens diameter. One side of the adapter attaches to the matte box and the other clamps onto the front of the lens, securing to it with a thumbscrew.
UPC: 840534116361