fet

This part came off an ESC on a drone. I think it's a fet but can't find any info..Please help.

hello, I have to build an automatic gain control using an FET and an Operational Amplifier, for a phototransistor (SFH314) so that when the signal of an IR LED is weak the AGC maintains the signal, and when the signal is strong reduces it, the gate of the FET I have to control it with the...