SIS Ergo M Series is a non-electric height adjustable table collection using a spring loaded system. M Series is perfect for mobile height adjustability. An integrated locking system allows for easy adjustment but no accidental adjustment. M Series comes in three base and top shapes with four weight ranges. M Series adjusts from 27.5″ – 44″ in height and is available on casters. Complete your ergonomic needs with a wall mounted or cluster application.