On Line Controls manufactures "MicroAir" ultra low air pressure regulators and controllers for tubing extrusion ID pressure control. They can regulate the pressure to an exact set point. Normal meter ranges are from 0-2" of water up to our maximum 0-5 psi. Pressure is maintained for widely varying flow rates such as when a cut or variation in windup processes. The "force balance regulator" provides instantaneous response to changes in flow rate and maintains a set pressure with flow rates from near zero upt to the rated maximum. Three models are available; the MicroAir I is a manual model controlled by a single knob; the MicroAir II which can accept contact closure inputs; and the MicroAir IV which is a high speed programmable unit with 0-10 volt input for bump and taper tubing. All units come in a stainless steel box with magnehelic display. Options are multi-channel units for multilumen tubing, digital display, and voltage outputs.