- The piston-type pressure regulator features aperfect regulating and compensating system that provides highly and consistently accurate delivery; - The relieving system keeps the pressure gauge reading constant even while pressure is being reduced; - Piston-type pressure regulation system; - Regulation knob with locking device and threaded fastening ring in engineering polymer; - All models are fitted with square gauge with 1/16 scale bar- 0/230 psi- (class 2.5).