Black Menba 1-8S Battery Checker With Buzzer Alarm Plus Cable Tie works with any 1-8S Lipo/Li-Ion/LiMn/Li-Fe Just plug into the balance plug and the LED will cycle through the individual cell voltages as well as list the total voltage You can set the alarm from 2.7 to 3.8V per cell or you can turn the alarm off Dimension: 1.5"(L) x 0.4"(H) x 1"(W)