I now believe due to it position in the circuit that it may be a thermistor. This unit was working fine before I left on vacation. When I returned and plugged the unit back in, it blew the fuse. THe component is blackened on one side. A thermistor is a sacrificial device that is used to protect the circuit. Thermistors are widely used as inrush current limiters or self-resetting overcurrent protectors. When I disconnect the LFE connection just before unplugging the unit I got a loud ground hum for a second and believe that may have been when the unit was damaged. However: I am still looking for info for this device. Does anyone have a suggestion as to where I might be able to obtain the specs for this?