I purchased 2 handsets of this model, charged the batteries according to spec, and then tried to register them with the base unit. Only 1 would register, the other never did.I tried to contact the seller, but no response. I bought these 2 replacement handsets because of problems with 2 of the original 3, purchased over 1 year ago. I have since disconnected the Uniden system, and purchased an vtech unit, which I am much more pleased with.