Reserve Strap, the accessory maker that started taking pre-orders for a battery strap for the Apple Watch had discovered that it is possible to access Apple Watch’s hidden port.

The port is hidden in the slot where the band connects to the device. They showed us how easy it was to gain access to the hidden 6-pin diagnostic port, and also announced plans to use the 6-pin diagnostic port in their battery strap to charge the Apple Watch instead of their earlier plans to use a magnetic, wireless charging solution.

They’ve just published a video, which shows that it is indeed possible to charge the Apple Watch using the diagnostic charger.

In the video, they charge one Apple Watch with the standard inductive charger that comes with the device, and charge another one with their own charger which makes use of the 6-pin accessory. The Apple Watch charges slightly faster (95% vs. 90%) with Reserve Strap’s charger that uses the 6-pin port.

https://www.youtube.com/watch?v=NOuUroPZE14

Lane Musgrave of Reserve Strap also points out there is no charging indicator displayed on the Apple Watch when it is being charged using the 6-pin port. They plan to include a simple LED on the Reserve Strap to indicate charging state. He also claims that “there was less ambient heat radiated on the back of the Apple Watch” using the 6-pin accessory port compared to the wireless induction mention.

It’s also worth noting that while the Reserve Strap plans to use this diagnostic port, Apple doesn’t encourage accessory makers to do this. It may do so in the future, but for now, the port is supposed to be for Apple’s use only; the company has actually designed a special strap that allows the device to charge while it’s on display in Apple Retail stores.

Reserve Strap’s battery strap for Apple Watch is available for pre-order for $250. Musgrave says they’re finalizing the design for Reserve Strap, and will announce a 2015 shipping date in the coming weeks.

I was expecting the Apple Watch to charge a lot faster using the 6-pin port, so little disappointed that it is only marginally faster. What do you think? Let me know in the comments.