Model AT4 is an extremely versatile 24 Hour 365 Day Event Timer designed to support a wide range of applications. Features/Specifications: 12 to 24 volts AC or DC operation, Standby current: 20mA with relays off combined with 40mA for each relay on, Four (4) Form “C” relay contacts are rated 10 amp @ 20VAC/28VDC, EE Prom memory protects against loss of programming due to power failure, Accurate crystal controlled clock (DC operation), Momentary and/or Latching Events, 254 individually programmed daily/weekly events, Block programming capacity can accommodate a total of 1778 events per week, 254 programmable Holiday events, “First man in” option, Alphanumeric LCD display simplifies programming, Standard or Daylight Savings Time settings, Automatic compensation for leap year, Each relay operates independently, Built-in charger for 12VDC sealed lead acid or gel type batteries, (Max charge current 300mA), Lithium battery backup maintains clock, User friendly keyboard programming.