Compact Wide Angle 2 x 4”x4” Metal Matte Box, 100mm Clip On. Comes with leatherette cover.

Ex BBC, can be used with screw in step down rings, none included, or straight clip on 100mm.

I have another one that I’m keeping, these are really nice matte box, heavy duty, think these were originally made by either Arri or Chrosziel.