A seat slide, also known as a seat glide or depth adjustment, is a mechanism in an office chair that allows the user to adjust the depth (front-to-back distance) of the seat. This feature is particularly beneficial for taller or shorter individuals, as it ensures that they can sit comfortably and ergonomically, with their backs against the backrest and a small gap between the edge of the seat and the back of their knees.

When engaged, the seat slide allows the seat to move forward or backward on a track, extending or reducing the distance from the backrest. This adjustment helps accommodate different leg lengths and sitting preferences, thereby promoting better posture and reducing the risk of discomfort or injury.

It's important to note that not all office chairs include a seat slide mechanism; it's often found in more advanced or ergonomically designed models among other chair adjustability functions.