Adjustable and releasably connectable lumbar support assembly

A lumbar support sub-assembly including a lumbar support band adapted to extend across the frame of a seat back rest having a pair of attachment means thereon, a pair of mounting means each at a respective end of said band, each of said mounting means being releasably connectable to one of said pair of attachment means on said seat back rest frame to permit said sub-assembly to be attached to and removed from said frame, said releasable connection permitting relative movement between the respective said mounting means and attachment means between a plurality of relative positions including a separable position, said respective mounting means and attachment means being separable only when in said separable position, said band including an operative portion extending between said mounting means, at least one of said mounting means having a static part which is engageable with one of said attachment means and a dynamic part which is attached to said operative portion and is movable relative to said static part whereby the effective length of said operative portion may be varied, and drive means operable to permit said dynamic part to be moved in either of two opposite directions relative to said static part.