Fairchild's Model 4500 Pneumatic Volume Boosters are popular due to their rugged design and high flow capacity in an economical package.  In its pilot operated regulator design, the M4500 handles up 250 psig, [17.0 BAR], (1700 kPa) supply pressure and has five available signal to output ratios to meet most control element requirements.  The 4500 Booster provides a flow capacity of 150 SCFM (255 m3/HR), which equates to a Cv factor of approximately 3.0 in both forward and exhaust modes.