TheNiSi C4 Cinema Filter Holder Kitis made of CNC machined aviation grade aluminium and is perfect for when you dont want – or need – the extra size and hassle of a matte box, but still, need filters. It allows for the convenient use of up to two, separately-available 4″-wide, 4mm-thick filters along with an included integrated CPL (Circular Polariser). The circular polariser can be rotated independently of the two front filters which allow for control over the amount of polarisation wanted. This holder allows cinema grade filters to be used without a matte box on lenses that have a front thread of up to 82mm with included adapters. adjust its effect. In such instances, an external dial on the adapter ring allows for the independent rotation of the circular polarizer. Adapter rings for lenses with 86mm or 95mm front filter threads are also separately available. This holder also allows the use of those same filters on stills lenses for both DSLR video and photography.