Tec Line: Cleanroom and ESD has a height adjustable back that provides 3" adjustment range for the back and lumbar. There is a Polished 20" Diameter with simple rotation/lock for height variation of the footring for the stool version or the base for cleanroom is a black nylon 5 star base. The base for Cleanroom/ESD is a polished aluminum 5 star base. Hard floor casters with soft wheel braking casters for hard floor are also standard specifications.
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