Wireless kit. Uses advanced 868MHz technology. Solar-powered siren uses daylight to maintain charge. Fully expandable system. Self-learning set up of accessories. Easy to install. Includes key fob. Expandable up to 24 devices. Specifications: Up to 125m open field range. Expandable up to 12 PIRs and 6 magnetic door contacts plus up to 6 remote keypads and key fobs.