A tape take-up hub which comprises a circular ring having an outer wall surface on which a length of magnetic tape is taken up and an inner wall surface defining an opening with which the ring can fit onto a driving shaft and formed with three key ways adapted to mesh with keys formed on the driving shaft, said ring having a thickness substantially equal to the width of the magnetic tape, the improvement which further includes, as additionally formed on either side of the circular ring, three protrusions of the same height and three recesses of a depth greater than the height of the protrusions and adapted to receive the corresponding protrusions of an adjacent hub of an identical structure. The protrusions and recesses are equally spaced apart along one and the same circle and are aligned in position to those formed on the reverse side of the same circular ring.