Model 2500 Grooved is a compact 300 PSI rated single-handle ball valve that eliminates the connections of the traditional assembly loop. Model 2500 now has a port to add a drain line from a pressure relief valve. This TESTanDRAIN valve allows you can add a pressure relief valve without draining down the whole system. This model does not ship with a pressure relief valve--for included pressure relief, order Model 2511A or order a kit to install separately. Model 2500 threaded model is available in sizes 1" and 1.25", and 2", orifice sizes K2.8-K25.2, and groove by groove connection. UL Listed & FM approved. Made in the USA.