Zomei? Square Z-PRO Series Filter Holder Support + Adapter Ring 67mm .The ZOMEI filter holder is specially adapted for two pieces of 100 x 100mm (4") or 100 x 150mm (4 x 6") Z series filters Lightweight filter holder allows the use of 4x4 or 4x5 (100mm) filters to be attached to camera lens Compatible with Cokin Z-PRO Series, need to work with Z Series holder and adapter ring The filter holder can hold up to 2 Z-PRO Series filters at the same time