Replacement 2 Volt 2.5 Amp Hour Alarm System Battery. Chemistry: Pure Lead. Dimensions: 1.35" Long x 2.68" Diameter. Weight: 0.4 lbs. Description: Steel Jacket. Terminal Type: F1 Faston. Alarm batteries of this type are typically used in home alarm systems, fire alarms, security alarms, medical monitoring alarms, car alarms and business alarms. Alarm batteries are used for back-up power in case of power outages or power surges. A fully charged and maintained alarm system battery can give you piece of mind that your alarm system if fully functional even without power. Your main alarm system back-up battery can typically be found in a battery panel located on the wall or in a battery bank possibly in a closet. Remember, if you have a wireless alarm system you may also have batteries to maintain in your remote key fob, motion sensors, strobe lights, sirens, transmitters or other devices. Other places to find alarm system batteries may be in back up lighting and fire and smoke sensors. . Battery Benifits. • Spill proof, valve regulated design allows for the installation of this battery in any position. • Absorbent Glass Mat (AGM) technology allows for optimal performance. • Excellant resistance to vibration, shock, chemicals and heat.