ATN Extended Life Battery kit can support your binoculars or monoculars for up to 15 hrs. 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.