10.95 volt 2 1/2 amp hour lithium ion backup battery for communication equipment.
It was in a Comcast modem that I paid rent for to Comcast every month
Ani I had to buy the Comcast backup battery. $35.
and when I quit Comcast I have this hi-tech battery which Comcast made me buy so that the modem would keep running during an electrical power outage
if you have Comcast this might be just the thing for you
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