This ND16 WMC 100x100mm Filter from Benro is a 4 stop neutral density long exposure filter designed to reduce all different wavelengths of light for an even 4 stop reduction in light. This allows your shutter speed to be slowed significantly, which is particularly useful when photographing water and tides, or when a dramatic effect is desired.
The WMC abbreviation is short for Waterproof Multi-Coating, which as well as being anti-reflective, makes this filter water and oil repellent and fingerprint and scratch resistant. This filter is 2mm thick and designed for use with the separately available Benro FH100 Filter Holder, however is usable with most 100mm filter holders.