Know your packs!  The EOS SENTRY is a quick, convenient, easy-to-use device. It shows at a glance the remaining capacity in your battery pack, cell balance, and other information you need to get the best performance and reliability from your batteries, and avoid costly mistakes.  

The large LCD display and capacity graphs make it easy on your eyes.  And the low price of the SENTRY compared with the high cost of batteries make it a sure money-saving addition to every toolbox at the flying field, boat races, or car race track.

Discharge of LIPO in particular beyond 80% of capacity is sure to damage them.  Be sure to use the EOS Sentry after flights (or laps) from time to time. If you see 19% or less capacity remaining, reduce the Transmitter timer until at least 20% is shown remaining at the end of each flight or race...