Bass guitar made by American instrument company Rickenbacker in 1961, serving a period of twenty years before being discontinued in 1981 in favour of the updated 4003 version. Despite not selling as well as the Rickenbacker 330, the 4001 has risen to arguably become Rickenbacker's most popular model in its history while also being one of the standard bass choices in progressive and classic rock as well as important blips in the post-punk and metal scene.