Heavy Duty Internal / External Keypad. With an LED indication, backlit keys and a dual output door mode, this vandal resistant Internal/External Keypad from Asec is a stylish and easy to programme digital access keypad which is ideal for heavy duty access entry solutions. Supporting up to 100 users with over 1 million pin combinations, this keypad also features a latching feature, adjustable output timer, and fixings for either wall or post mounting.. Back lit keys. Up to 100 users. Latching feature. Vandal resistant