The Visonic XCELPLUS Extended Life model is a high capacity battery backup for your PowerMax MCS-720 indoor siren bell box. The Extended Life model is recommended for anyone that requires more hours of backup from their sirenand doesn't want to replace the battery for the next 4-5 years.

The Visonic XCELPLUS Standard model is also suitable for the latest PowerMax series alarms, but may only offer 2-3 year life depending on the frequency of use.

The Visonic XCELPLUS Extended Life and Standard model battery are compatible with the MCS-720 bell boxes. The XCELPLUS Extended Life is the highest capacity battery available on the market for the MCS-720 bell box and unlike budget consumer batteries, it's produced using the highest capacity 20,000mAh lithium thionyl chloride (LiSOCl2) battery.

The MCS-720 bell box can accommodate 2 batteries for longer lasting life. Each siren must have 1 battery installed, but Visonic recommend installing the optional second battery for greater back up duration and less maintenance. To conform with UL installations, 2 batteries per siren must be installed.