Abstract: An anti-rollback system allows wheelchair users the freedom of travelling up and down inclines without enlisting the assistance of others to do so and includes a pair of non-rotatable axles fixed to the frame of a wheelchair, a pair of wheel hubs, each of which includes two sprags or one-way clutches mounted in opposing rotational directions therein, and a shifting mechanism for selectively engaging either or neither sprag with the associated axle. The user may thereby select normal free-wheeling operation of the wheelchair or anti-rollback in either the forward or reverse direction.