This Disc base series offers height range adjustability of approximately 11-7/8". This base travels from 27-1/4" to 38-3/4", and fully meets ADA height requirements. The Disc Base has a very low profile and is an excellent choice when you are trying to reduce the visual size of the tables or eliminate a person’s feet from hitting the typical base mass. Adjustment is easy. Simply set your foot on the base and lift the surface. The mechanism will automatically adjust to the next level. To lower the surface, lift it to its highest level. It will release and slowly descend to the lowest position. No locks, no levers, no cranks, no cylinders, no pins, etc. Base heights are numbered for easy leveling. This base series offers one of the most user friendly, multipurpose, and cost-effective lines of adjustable height bases and mechanisms available today.