Easy to install – no wires or cables.| No signal interference for neighbours.| Each chime and bell press are factory set pairs and are not interchangeable with other HPM door chimes or bell presses.| A simple, battery operated door chime.| With no wiring, you can place them wherever you wish.| Or carry them with you so you never miss a delivery, nor visiting friend.| Featuring a flashing light function, they are useful in circumstances when you cannot hear the door chime tune.