For those of you flying without any fancy telemetry this is a great product for knowing what your battery level is up to 400' away. Mine arrived in the mail today and worked great! I am still going to use a timer just in case for a while, but I set it for 3.6v and it did exactly what it was supposed to do and for the price you can't go wrong and its less annoying than a loud buzzer in the sky!
https://www.hobbyking.com/hobbyking/sto ... duct=40033
https://www.hobbyking.com/hobbyking/sto ... duct=40033