NiSi 100mm System V2--Adapter ring for NiSi 100mm System V2- Filter Holder (62mm) NiSi100mmSystem V2--Adapter ring 62mm for NiSi100mmSystemV2- FilterHolder Made from aviation-grade aluminum with single element processing by CNC machine With matte black frosted finish on the surface All of the screw accessories are made of copper and with black nickel plating. Sturdy and durable