We added a 3-LED on-board battery checker to our best selling Soft Mount One-Piece Charge Switch. The three LEDs - green, yellow,& red - monitor the status of Rx pack under actual load. It is compatible with both 4.8V and 6V flight systems. Mounting cut-off area for this switch is 1.3" x 0.5".
Charge Switch with On-Board Battery Checker