CQR FI/CQR983-CO conventional 12 Volt CO DETECTOR
[FI/CQR983-CO/12]

Easy fit, compact, stylish, unobtrusive. The only problem is that there is the U it does not have a Test button on it. I have installed three of these into my intruder alarm panel and they all light up as they should. The only way I have found to test the wiring back to the control panel is to twist the detector off the base to open the circuit. Sadly this does not test the onboard relay or onboard sounder. If you are looking for a detector you can test easily don't buy this one!