UPG’s Sealed Lead- Acid Batteries are the number one choice for use in the Battery Backup System. They are both durable and long lasting, made with Absorbent Glass Mat (AGM) technology for superior performance. Valve regulated, spill proof construction allows safe operation in any position. Approved for transport by air. D.O.T., I.A.T.A., F.A.A. and C.A.B. certified.