Genuine Arris 5-8 Hour Touchstone VoIP Modem Gateway Backup Battery for Docsis 3.0 Docsis 3.1 (Supports Phone Servcie During Electrical Outage on Modem NOT Internet Service) ARCT02220B BPB026S
Brand: __Arris

Supports various Models including; TM502G, TM504G, TM602G, TM604G, TM608G, WTM652G, TM722G, TM802G, TM804G, TM822G, TG852G, TG862G, TM1602G, TM3202G, TG1662G, TG1672G, TG1682G, TG2472G. PLEASE CHECK YOUR MODEM PRODUCT MANUAL FOR SUPPORTED BATTERY TYPE.

Battery Backup supports only phone service provided by your service provider on the modem.
Internet Service is not supported on Battery Back-Up.
Backup Hours vary by Modem model number.
During electrical outage make sure an analog phone is plugged into the Phone Port of your modem. Dect phones are not supported by modems in case of electrical outages