The Vuzix M300 On-Frame Battery is compact and balances the original M300 Smart Glasses on all Vuzix frames. It includes a micro USB charging port, power indicator LED light and custom pogo-pin connector for connecting the cable back to the M300 unit. This on-frame battery provides two to three hours of power and is hot-swappable for continued all-day use of the Vuzix M300 Smart Glasses.