Aico EI2110 multi-sensor alarm with rechargeable battery back-up. It contains two separate sensing elements optical and heat. As the unit monitors two different by-products of fire, its response to all fire types (e.g. fast flaming, slow smouldering etc.) is vastly improved over traditional single sensor alarms. Additionally, its resistance to false alarms is also increased. This is further enhanced by the unique dust compensation feature that automatically adjusts for any contamination within the optical sensor chamber. The alarm runs on 230V AC mains power and has built in tamper-proof rechargeable lithium cells that act as a battery back-up in the event of mains failure. These rechargeable lithium cells are designed to have a minimum ten-year life and outlast the life of the alarm itself. They provide up to six months alarm operation without mains power. The alarm also has remote control capability allowing the alarm to be controlled remotely from an alarm control switch. This allows alarm test, locate and silence functions to be performed from floor level. If it is also interconnected to other series mains powered alarms, then the whole system can be controlled remotely. Up to 20 alarms can be interconnected which will cause all alarms to sound when one unit senses fire. A manual call point (MCP401 RC) is also available. The alarm is supplied with an easi-fit base that allows quick and simple installation of the alarm, combined with simple alarm head removal and replacement. The easi-fit base automatically connects both mains power and battery back-up as the alarm slides on. The alarm can also be fitted to an RadioLINK base to allow wireless interconnection of alarms and connection to additional RadioLINK devices.