Abstract: Movable back supports that can be moved in many different axes about a seat and fixed in a position desired by a user are contemplated. Movable back supports comprise sliding members, straps, and a tightening mechanism that alters tension in the straps. Contemplated movable back supports can be positioned at a desired height relative to a backrest and at a desired distance from backrest rails of the seat. Furthermore, contemplated movable back supports can be moved forwardly into a back of a user or rearwardly away from the back of the user.