To obtain reliable performance use only AAA Energizer Ultimate Lithium 8x batteries (L91). For optimal performance, please try and utilize SPOT in locations with a clear view of the sky with the logo side up.
Extreme heat/cold and trying to send messages indoors or under extreme canopies can drain battery life. If the On/Off indicator light blinks red this is a warning your battery is about to die. Always carry extra batteries with you. Test your SPOT device before each trip by sending a Check-in/OK message.
Proper battery selection is critical for the best performance.
For more information, please refer to the chart linked HERE.