Sony HXR-NX100 Camcorder Battery Lithium-Ion (4600 mAh) - Replacement for Sony NP-F770 Battery Replacement battery for the Sony NP-F770, Lithium-Ion (Li-ion) 7.4V (4600mAh) 100% compatible with your OEM battery - 3 year warranty. Made with high quality Japanese cells. Synergy Digital is a Registered Trademark