This is the ADT TS Keypad that comes with the new ADT Pulse TS System. If you want to add another one or if you need to replace the one you have you can order this. It comes ready for a desk mount but if you want to mount it to the wall you can purchase the plate and plug for that. If you have one already and you just need a new battery for it you can get it here.
Below is a picture of the front cover pulled down to reveal the push buttons.
One thing cool about the ADT TS Keypad is that the front cover plate is magnetic and can be removed very easily. Since it is the first alarm keypad to use magnets to connect the front plate it has a nice cool feel similar to one you would expect from Apple with their iPad covers.