Our's was 4515 ad seven others shared the line, there was an older lady down the road from me who picked up the phone no matter how many rings there were and listened in. The phone rang 3 short rings together in a group for our house, One day the woman came hurrying to tell mom and dad that my dads brother was on the phone from buffalo and they were down below the house at the time, but she swore she never listened in.