The components of a rack and pinion gate are the shaft bearings, pinion shaft, rack(s), pinion gear(s), gate frame, and manual or motorised shaft drive.

A rack and pinion is a kind of linear actuator in which a linear gear (the rack) is engaged by a circular gear (the pinion). When combined, they transform rotational motion into linear movement. The rack is driven in a straight path by rotating the pinion. On the other hand, if you move the rack linearly, the pinion will rotate.