Don't let yourself be stuck without a functioning unit, because you didn't bring extra batteries to power your device. ATN Extended Life Battery kit can support your binoculars or monoculars for up to 15 hrs. You can use your devices longer and save money and the environment in the process. Enjoy your activities all day long - whether scouting, camping, bird watching, or surveillance. You can even power your none ATN devices, which are compatible with a micro USB. Designed to be used with the ATN line of Smart HD Optics: BinoX-HD, OTS-HD, and BinoX-THD. Included: 10,000 mAh Battery Pack; USB to Micro USB w/ L Shape Connector