Before using the unit for the first time, we recommend charging the battery in the Seal. Charging is performed by attaching the end of the charging cable with 2 pins and a magnetic circle to the back of the Seal unit and the USB side to a USB port as shown below. 

if charging is in progress, an orange LED will be turned on . When charging is completed, the red LED will turn off.

Never attempt to charge or connect while there is water in the charging area. The Seal is only designed to be used with the provided charging cable. Usage of third party charging cable are not recommended and will void the warranty.