Please read the profile section and product page to the end before considering a purchase. Used for several years. The call button was attached to the front door. The receiver that plays the call sound is a plug-in type, so it doesn't require batteries. The call button generates power every time it's pressed, so it also doesn't require batteries. The call button was adhesive-backed, so it peeled off when removed. There are several different call sounds. There's also a call sound that says "Please come to the room," so it can be used for caregiving. This is a used item, so please consider this before purchasing.