Originally Posted by
ATX SRT-6

Or, you can get a pair here less cost with free delivery ( http://www.ebay.com/itm/2Pcs-Ni-MH-Button-Rechargeable-Battery-3-6V-150MAH-PLC-Data-backup-power-2P-1P-/221023510118?pt=LH_DefaultDomain_0&hash=item3376071e66 ).
.