The Vari Mister has a built in valve to control the flow and pattern size of the spray. This makes it useful in a variety of applications. It has a maximum diameter of 36" and can be shut off when not in use. The maximum flow ranges from 4 GPH at 10 PSI to 7 1/2 GPH at 30 PSI. It has a 10/32 threaded base for use in 1/4" tubing or with a Rigid Riser.