Access control and alarm monitoring systems; Accumulator boxes; Accumulator jars; Accumulators and batteries; Accumulators; Accumulators, electric; Accumulators, electric, for vehicles; Acoustic alarms; Acoustic amplifiers; Acoustic amplifiers for mobile devices; Acoustic conduits; Acoustic coupling devices; Acoustic membranes; Acoustic separation units; Alarm central units; Alarm installations and alarms; Alarm monitoring systems; Alarm sensors