Lenel ABT-12 BATTERY KIT 

ABT-12 Lenel Battery Kit, includes, 12 VDC, 12 AH Battery (PS-12120)
Built-in charger for sealed lead acid or gel type batteries (Optional ABT-12) Automatic switchover to standby battery when AC fails Maximum charge current 0.7 amp Low battery and battery presence supervision (form C contacts) AC fail supervision (form C contacts) Zero voltage drop when switched over to battery backup.