The RB840 is a "Deluxe" edition Roadstar II Bass series solid body electric bass model introduced by Ibanez for 1986. It was produced in Japan.
The RB840 features a double-cutaway basswood body bolted to a maple neck with a 24-fret rosewood fingerboard with pearl dot position marker, side dots and a matching headstock. Components include a PJ pickup configuration with a P50 on the neck position and a J50 on the bridge position, an Accu-cast B II bridge with 19mm string spacing, a graphite nut, Ibanez Smooth Tuner BII tuning machines and Ibanez "Dead End" strap buttons.