Price is per pair. Directional locks for the casters make it possible to roll the TRAM straight down the hall without drifting laterally. The locks can be inserted into any or all of the four casters, although two should be sufficient to ensure a straight path. With the lock released the casters are free to swivel, allowing for maneuvers in tight spaces. If the TRAM is going to be used for early mobilization in the ICU, directional locks would be advisable.