System Sensor InnovairFlex Duct Smoke Detector

Got this System Sensor duct smoke detector up for grabs. It's the kind used in HVAC systems to catch smoke in the air ducts. The clear cover is nice because you can actually see what's going on inside without taking it apart. It was pulled from a working environment but I haven't tested it myself lately. Good for a replacement or if you're working on a shop project. It's got some dust on it but looks solid.