The Gibson Les Paul Jr. is a solid body electric guitar introduced in 1954 as an affordable, entry level Les Paul

Gibson Les Paul

The Gibson Les Paul was the result of a design collaboration between Gibson Guitar Corporation and the late jazz guitarist and electronics inventor Les Paul. In 1950, with the introduction of the Fender Telecaster to the musical market, electric guitars became a public craze. In reaction, Gibson...

. It was first released with a single cut body style however models with a double cut body style were later introduced in 1958.
The goal for the Les Paul Jr. was to have a high-quality guitar that was still affordable. For this to happen, the Jr. was stripped down to the basics; one pickup, one volume knob and tone knob.