The Potter VSR-CR is a vane type waterflow switch for use on wet sprinkler systems where external corrosion is a concern. It is UL Listed for use on steel pipe. Models available for pipe sizes 2" through 10". The Potter VSR series is the industry standard for flow switches for fire sprinkler systems and is compatible with the widest range of pipe schedules (5 through 40) in the industry as well as all necessary listings and approvals for installation worldwide. Please see the individual data sheets for specific information about a particular model and size, including the VSR-CR-10 for use on 10" pipe.