Absorbed Glass Mat technology for durability Spill proof and maintenance free design 1 year warranty High performance replacement battery These are replacement batteries for PS-1250-F2 HR1221W RT1250-F2 NP4-12-F2 HR5.8-12 and UB1250-F2 (D5777). We supply only brand new factory fresh high quality batteries. We guarantee the best price and 100% compatibility with your OEM model. You must use the existing cables and hardware to connect your replacement ups batteries. The replacement sla batteries also include a minimum of one year warranty.