555 LDR EXP
An automated expression pedal. A 555 timer-based LFO controls an LDR connected to a TRS jack. The two big knobs control the rate and (to an extent) the waveform, while the small knob controls the base level of current to the LDR LED. The left switch toggles between the internal LDR, the external LDR and both in series. The right switch is an on/off switch.
I don’t remember what CFG stands for.