When should you replace the gas cylinder on a drafting chair?

A Class 4 gas cylinder on a commercial drafting chair typically lasts 5–8 years of daily use before the seal fails — you'll notice it when the seat slowly sinks while you're sitting. Replacement cylinders run $20–$60 and take 5–10 minutes to swap with a pipe wrench. FindOfficeFurniture.com carries replacement cylinders for the chair brands we stock — call 888-719-4960 for parts help.