The Battery Pack has four LEDs located above the WHOOP logo on the top of the device.
Red/Green Charging LED
The topmost oval-shaped LED will remain off unless attached to a USB charging cable that is plugged into a power source. This LED will then illuminate to show the current charge status of the Battery Pack. Once the Battery Pack is fully charged, it should be able to completely charge the WHOOP Strap.
Solid Red = Charging
Solid Green = Fully Charged
Note: There is no indication of the specific charge level (%) of the Battery Pack; it is either charging or fully charged.
The other three circular lights on the Battery Pack replicate the same light patterns that are presented by the LEDs on the side of the WHOOP Strap.
As a result, these LEDs indicate the battery level of the WHOOP Strap and/or present indicate the pairing status of the Strap. In other words, these LEDs only describe the status of the Strap.
For a detailed description of all possible LED patterns, check out this article.
Shortly after sliding the Battery Pack onto the Strap, the Battery Pack will briefly display the Strap's battery level via the three white/red circular LEDs. After a few seconds, these LEDs will turn off and remain off unless the Strap (and battery pack) is double tapped.
Note: If you see a combination of red and white LEDs, this indicates the Strap needs to pair with your mobile device. Check out this section for help re-connecting your Strap to your mobile device.