Hobbico Voltwatch 2 4.8V 6V RX Monitor FEATURES: 7-LEDs provide instant, accurate battery voltage status of Low, Safe, or Max; Only one LED glows at a time Small switch to select 4.8V or 6V INCLUDES: One VoltWatch2 On-Board Receiver Battery Monitor w/Futaba J plug One 1.5 x1 piece of double sided mounting tape REQUIRES: Plugging into any unused receiver port Mounting onto the airplane with double-sided tape