Its the same plastic used on all different types of buttons. Its one of the best designed buttons out there-really reliable-very easy to change out. The only issue Ive had is if the cleaning crew uses an acidic cleaner on their bronze or stainless. After some time the acidic cleaner tends to eat away at the plastic ring. The non-serial link style button is a pain. Its very hard to wire up as the contact clamps for the wires are in odd spots
