Explainer
S Track vs L Track vs SL Track
The track is the rail the rollers travel along. Its shape decides how much of your body the rollers can actually reach.
By ChairMentor Editorial Team · Updated 2026-08-22
S track
An S track follows the natural curve of the spine from the neck to the lower back, then stops. It keeps the rollers in contact with the spine's curvature but leaves the glutes and hamstrings untouched.
L track
An L track continues past the lower back and under the seat, extending coverage to the glutes and upper hamstrings. Track lengths are typically quoted in inches.
SL track
An SL track combines both: the spinal curve of an S track plus the seat extension of an L track. It is the most common configuration in premium chairs.