This NiSi Filter Holder Kit allows for the convenient use of up to two separately available 100mm wide, 2mm thick filters, along with an included circular polarizer on a Venus Optics Laowa 12mm f/2.8 Zero-D lens. This kit comes fully assembled and features an aluminum-alloy filter holder that is pre-installed with two pairs of plastic filter slots, a configuration that accommodates two rectangular filters. Each slot is designed to grip an installed filter only along the surface of the filter's edges.