Professional Model with dedicated amplifier. Gibson, which acquired Epiphone in 1957, designed this guitar equipped with the controls normally found on an amplifier. Known as the Professional, this guitar was essentially a thinline hollowbody with f-holes, one mini-humbucker pickup in the neck position – and a variety knobs and switches mounted on the pickguard. The companion amplifier had only a volume control and an output cord, permanently wired to the amp, with a multi-pin connector that plugged into the Professional, which was also wired with a standard output jack. Due to its configuration, the amplifier could not be used with any other guitar. This is a rare model, with approximately 400 made. OHSC