Skip to content Skip to navigation menu


Prep-Air® II P3RA Series High Flow Precision Regulator

Item #101738842
    Shipment Options

Product details

  • 3550 Series Manually Controlled Precision Regulator
  • 1/4 NPT
  • 40 SCFM
  • 150 psig
  • w/o Gauge


  • Designed for applications that require high flow capacity and accurate process control. A poppet valve, which is balanced by utilizing a rolling diaphragm, ensures a constant output pressure even during wide supply pressure variations. Stability of regulated pressure is maintained under varying flow conditions through the use of an aspirator tube, which adjusts the air supply in accordance with the flow velocity.


  • Test equipment
  • Gas mixing
  • Valve operators
  • Positioning cylinders
  • Laboratory equipment
  • Web tensioning
  • Clutch and brake controls
  • Roll loading
  • Test panels


  • Diaphragm design for good repeatability, response and sensitivity
  • Two full-flow gauge ports
  • Precise regulation
  • High flow capacity
  • Dampening action of aspiration tube makes regulator insensitive to changes in flow
  • 0.1 psig change per 100 psi input pressure change


  • None


Port Size 1/4
Body Size 1/4 in
Operating Temperature [Min] -40 °F
Series 3550
Pressure Limiter No Pressure Limiter
Pressure Range [Min] 2 psig
Gauge Port 1/4 in NPT
Port Type NPT
Flow 40 SCFM
Preset/Limiting Pressure N/A
Inlet Pressure [Max] 500 psig
Size Designation Basic
Knob Color Black
Control Type Manually Controlled
Relieving Relieving
Pressure Range [Max] 150 psig
Body Material Aluminum
Operating Temperature [Max] 200 °F
Has Gauge No
Regulator Precision Precision
Component Regulator
Preset No Preset
Adjustment Type Knob
Reverse Flow No
Weight 1.6 LB
Close Compare List Open Compare List Toggle

Product Comparison