Sealed Lead Acid battery. 2 contacts on top. 12 Volt SLA UPS Battery. Fits models; APC AP1250, APC AP1400, APC BackUPS 1250, APC SmartUPS 2000, Best Technologies BA-39, Best Technologies LI-1020VA B, Best Technologies Micro-FERRUPS FE1.4KVA, Data Shield AT800 (new), Data Shield ST675, Data Shield Turbo XT300, Data Shield Turbo XT350, Del