The 4000 model resembled the “S” model 4001 in that it had no body binding and dot fretboard markers; however, after 1972, the 4000 series usually had a “glued in” neck, as opposed to the “neck thru” construction of the 4001 model and had only a treble pickup and no neck pickup. This early 1973 (serial # MB) had the desirable gap-tooth cast aluminum tailpiece that was phased out shortly thereafter. This bass has been refinished in Jetglo and comes with its original case.