What synthesizer did the Beatles use on Abbey Road, and why is it significant?

The Beatles used George Harrison’s Moog IIIp on Abbey Road. It’s significant because the album is rock’s first serious embrace of the Moog synthesizer, with iconic sounds on tracks like “Because,” “Here Comes the Sun,” and “Maxwell’s Silver Hammer.” Harrison brought one of the earliest units to the studio in 1969, and despite some band frustration, the album proved the Moog could do more than novelty or spaceship sounds.