OASE ShutOff Valve 16/22 mm for the OASE FiltoSmart 200, FiltoSmart 300, BioMaster 250 through 850 Filters and OASE ClearTronic UVC 7W UV Clarifier. OASE ShutOff Valves for External Aquarium Filters makes routine filter and tubing maintenance quick and easy. Install in-line on the tubing between the filter and the aquarium. Designed with dual flow control and a disconnection feature that ensure no accidental spillage or messy maintenance. The ShutOff Valve 16/22 fits 16/22mm (inner/outer diameter) tubing. Can be used with the OASE FiltoSmart 200, FiltoSmart 300, BioMaster 250 through 850 Filters and OASE ClearTronic UVC 7W UV Clarifier. 8.3 inches in length.