The Brand, LEFC (large electronically adjustable proportional pressure compensated flow control) is an electronically controlled version of the original large FC51 style flow control valve. The LEFC performance as a flow control is very similar to the large FC51 because they both use the same spring and compensator spool. Thus, the control flow port (CF) and the excess flow port (EX) remain usable and pressure compensated. The main advantage of the LEFC over the large FC51 is that the flow can be adjusted proportionally with a solenoid instead of manually. The orifice spool proportionally opens as the current through the solenoid increases, thus increasing the flow out of the CF port (similar to positioning the rotary side lever on the manual FC). The solenoid is connected to our optional EC - series controls which can be sold with the LEFC. Please see the Electronic Controllers section for your control needs. We also give the choice of coil voltage, coil terminal and maximum flow setting.