a selectively lockable caster with total locking as well as directional locking functions . a separate lock tooth for each locking function is adapted to engage certain differently configured lock recesses . specifically , a total lock tooth , which is part of a mechanism that also applies a brake to the wheel , is configured to engage any of the total lock recesses and any of the directional lock recesses to lock the wheel against pivotal movement about the swivel axis in any of a plurality of total lock positions . a directional lock tooth is configured to engage only the directional lock recesses to lock the yoke against pivotal movement about the swivel axis in at least one directional lock position while allowing the wheel to rotate .