Office Chair Gas Lift Stop Collar
A snap-on split collar that stops a sinking office chair: it clips around the exposed chrome gas-lift piston rod (fits rods up to 30 mm through a 27 mm funnelled throat) and bears the seat's weight in pure compression on the cylinder or cover rim. 54 mm OD, 30.3 mm tall for ~28 mm of lift per collar, with a cone-in-cone spigot so two or three stack to set any height, and a 4 x 2 mm groove around the outside for a zip tie so it can't drop off. Replaces the split-PVC-pipe hack; no need to pull the seat off the chair.
desk office-chair gas-cylinder repair