Dogtra 4500 EDGE Manual De Instrucciones página 51

* The transmitter and receiver/collar rubber-charging cap ensures dirt
and debris does not build up in the charging port area. The unit is
waterproof even if the rubber-charging cap is not fully closed.
To charge multiple receivers/collars and a transmitter, combine
additional battery charger splitter cables as shown.
* Warning
3. Fully charge the unit before storing for one month or longer.
4. Always use Dogtra approved charging adapters. When the wrong
charging adapter is used, the LED indicator will not turn on or blink
amber.
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