The NiSi 77mm adapter for NiSi 100mm V5/V5 Pro/V6/C4 permits the use of 77mm filter thread lenses to be used with the NiSi 100mm V5 , V5 Pro, V6 or C4 Holder. It features a lightweight, aluminum-alloy construction that has a corrosion-resistant, black anodized finish for durability.