Pax-ii 800 most commonly refers to a door controller used in Otis elevators. There is also a widely known Vatech PaX-i series of dental X-ray systems. 博泰醫療器材股份有限公司 Pax-II 800 Door Controller (Elevator)
Correct adjustment of the toothed belt tension is critical for smooth operation and longevity. Pax-ii 800 Manual -