I changed this over with the existing wired doorbell which no longer worked, I'm guessing due to the contacts inside wearing out. I've not had much experience in wiring, but it was really easy to install, works perfectly and the LED illumination is a real bonus, especially during dark winter nights when you're expecting more ÍøÆغÚÁÏ packages, the delivery drivers really can't miss it! This review is based 3 months after installing, and it's still working perfectly.