the coverage is very good. we put in one end of the house and we called it from the other end. it was working fine.then we tried from the neighbour. still working. the intructions are not enough, there some buttons , still i dont know what they are. it doesnt have different channel for each they... the coverage is very good. we put in one end of the house and we called it from the other end. it was working fine.then we tried from the neighbour. still working. the intructions are not enough, there some buttons , still i dont know what they are. it doesnt have different channel for each terminal. they start to ring together. sometimes it gives different sounds. but it works fine. battery cap hardly opened. its great present for a grandma.they will not only call you for asking where their keys are. its a nice one. if your interested, there are models with more terminals Read more

around 433MHz - good range - PLL receivers The receiver responds very qick I like two LEDs on the transmitter I also like the alarm sound Buttons on the receiver do nothing , I believe the keyring will fall off of the receiver very soon The receiver uses 2 batteries I believe it should use only I... around 433MHz - good range - PLL receivers The receiver responds very qick I like two LEDs on the transmitter I also like the alarm sound Buttons on the receiver do nothing , I believe the keyring will fall off of the receiver very soon The receiver uses 2 batteries I believe it should use only one Not too loud siren Receivers not protected against water or moisture I just received this item . Did not bother reading instructions as usual :D It works great as it should . When you turn on one receiver LED starts blinking and the receiver is beeping , than you press one of the buttons on the transmitter . The receiver stops beeping . Turn on another receiver and press another button except if you want both receivers to respond on one button . I wonder how much the batteries in the receiver will last . The receiver has two chips (yes I just could not resist to open it ) , one crystal , and a resonator built in so the frequency is crystal locked around 433MHz . The build seems good to me , however I would not recommend exposing it to moisture . Great product , will order one more this instant . Thanx DX Thanx DX you did it again :D Will buy another one this instant Read more