A Yale Dummy Siren Box supplied with the SR system I purchased some time ago. Its not system dependent so its just whether you like the look of it or not. Its fitted with a small DIY installed LED strip (non flashing) that is powered by 4AA batteries, battery holder and new batteries included. It just rests in the unused D size battery box, taped in. If you don't want to bother with batteries its easy to hook it up to a 6v power supply.
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