QUAD buttons are square shaped premium quality push buttons to work with various COPs and LOPs together seemlessly. 8 LEDs illuminate the transparent button icon and the outer square frame evenly(if the button has braille bumps they are also illuminated). 4 spring loads on each corner generates required force for EN81-70 standards. Locking mechanism system doesn’t require any screws and can be easily attached or detached. High quality tact switches are used to ensure a long life span of usage. Various braille or standard figures like numbers, letters and function icons are available. Different types of buttons also available for various purposes.