This fit my 1500PFCLCD UPS perfectly and is a genuine CyberPower product. Check whether your unit has the "RB1280X2A" or the RB1280X2B battery in it before ordering a replacement. MY UPS MANUAL HAD THE WRONG REPLACEMENT PART # LISTED. Newer versions of the 1500PFCLCD UPS use the "B" battery. Older versions apparently used the "A" battery. The difference is that the "B" version has a cute plastic frame that holds the two batteries together and contains a connector. The "A" version has battery leads.