These vinyl ESD chairs feature proper grounding, conductive, and dissipative static control materials and have been tested to meet ANSI or ESD-STM-12.1-2006. Additional ergonomic benefits include a contoured waterfall cushion and an adjustable backrest with lumbar support for increased comfort during extended sitting durations. seat tilt provides 8 forward and 3 backward locking tilts for ergonomic posture support. These high bench height ESD chairs feature several customizable options, including your choice of ESD casters or glides on a polished cast aluminum base, and static-dissipating color configurations.