I believe the original CA-UGLY is a fixed 20db preamp and the tiny L R trim pots are for attenuation. Mine seems to have a light bulb for on and off inbetween the L R pots but no switch.
That describes the standard build. The two original CA-UGLYs I have are like this.
On/Off is via insertion/removal of the mic input cable or the battery. LED indicates power on. No on/off switch, no clipping indicator LED.
Some had power switches included by request as pictured in the thread willndmb linked above, but that was a non-standard option.