Proportion-Air manufactures the packaged F-Series FCV, a proportional flow control valve that consists of an electronic pneumatic positioner, a pneumatic valve actuator, an LVDT position sensor to continuously monitor valve position, an angle seat valve, and a parabolic shaped linear valve trim. These valves fit pipe sizes from 0.25" to 1.5", and permit flow ranges from as low as 1-20 scfh to 25-250 scfm. The company's basic flow control valve allows a maximum Cv of 19, as well as an integral closed-loop position with +/-0.3% F.S. resolution; analog outputs of 0-10 Vdc and 4-20 mA are available.

South Bend Controls custom-designs and manufactures pneumatic valves and accessories for customer-specific applications. They produce 2- and 3-way valves for pressures from 50 to 6,000 psi, such as aircraft, undersea, and industrial applications; these can be designed in several ways, such as poppet, manifold, coaxial, etc. The company also makes special valves, such as its high temperature pneumatic solenoid valve, pilot-operated anti-ice solenoid valve, and squib-actuated valves, for fast emergency flow of pneumatic gases (<5 ms).