The RPJ-312 Adjustable Precision Jets produces a delicate, clear stream of water. The Precision Jet comes with an integral adjustment feature to allow a variety of spray angles (0-15 degrees off center axis). The RPJ-312 are of three-piece machined brass construction, orifice size, adjustable to 15 deg. off vertical in a 360-deg. cone, 3/8″, 1/2″, or 3/4″ (M) threaded connection. Fine screening at the pump is recommended to minimize nozzle clogging. Please refer to the cut sheet for technical and hydraulic data, as well as the optimum water level. This is the jet used in the Roman Fountain Spray Rings.