Any ergonomic product ??? whether it???s a desk, chair, keyboard, monitor, or accessory item ??? should be able to be used by workers ranging in size from the fifth percentile female (4 feet, 11 inches tall; 113 pounds) to the 95th percentile male (6 feet, 2 inches tall; 246 pounds).??? What this basically means is that for many products, adjustability is a must.