Replacement battery fits 6 AT&T compatible models. Specifications: 5600mAh, 7.4V, Li-ion. Compatible with: ARRIS NVG589, ARRIS NVG599, ARRIS NVG589 VDSL2 Gateway, Frontier NVG589, U-Verse NVG589, NVG599 Gateway. Replaces: ARRIS 586185-001-00, ARRIS 586185-002-00, AT&T 586185-001-00, AT&T 586185-002-00. AT&T replacement battery designed for Cable Modem devices.