The Blacklight is a 6.6 x 6.6" clamp-on matte box designed for large zoom and ultra wide lenses. It has a 162mm lens clamp attachment which can be downsized via a variety of reduction rings. At max diameter, it'll cover lenses as wide as a Zeiss 8R mm rectilinear and RED Pro Zooms at 5K.
 
Blacklight features a Bright Tangerine patented 2-stage to 3-stage adjustability system, which consists of three filter stages, one of them hidden. At the turn of a few screws, you can slide open a section in the rear and reveal the third stage. All the stages accept 6.6 x 6.6" and 4 x 5.65" filter trays.
 
Blacklight also supports an optional rod-mount swing-away bracket and arm assembly for more efficient lens swaps. This bracket is used simultaneously with a clamp lens attachment.