The ESL Series battery units combine long-life expectancy, high performance design and a reasonable initial cost outlay. Ideally suited for a range of commercial applications, the long-life lead acid battery is specifically recommended for environments where the unit will be exposed to large variances in ambient temperature.SPECIFICATIONS:- Rugged steel cabinet with corrosion-resistant undercoating - Removable front panel on cabinet provides easy access and allows unit to be mounted at ceiling height - Solid-state pulse-type charger – current-limited, temperature-compensated, short-circuit proof and reverse-polarity protected. - Unit comes standard with electronic lockout and brownout circuits - Sealed dust-proof transfer relay, test switch and LED indicator lights - Long-life, maintenance-free lead acid battery - NEXUS compatible