These cleanroom or ESD chairs have been tested to Fed Std.209E, ISO 14644-1 (Class100 or ISO Class 5), and ANSI or ESD-STM-12.1-2006 standards and feature proper grounding, conductive, and dissipative static control materials. Optional 6-way adjustable armrests support a variety of arm placements for proper ergonomics. Additional ergonomic benefits include a contoured waterfall seat cushion and an adjustable backrest with lumbar support for increased comfort during extended sitting durations. A vinyl cleanroom or ESD chairs are constructed of highly durable molded polyurethane foam cushioning covered with easily cleaned static-dissipating vinyl in either blue or black. Optional seat tilt provides 8 forward and 3 backward locking tilts for ergonomic posture support. These high bench height chairs feature your choice of ESD casters or ESD glides on a polished cast aluminum base.