Cheap enough to have one in every room. While I can't speak to battery life just yet, for now it can show current CO levels each time you press the test button. The display also lights up when it's in the alarm state, which is nice. I will update if the battery life doesn't reach at least 90 days (I know CO monitoring uses a lot of power so I reasonably assume the batteries will need to be changed about every 3 months). But for the price, it's excellent value for money. No false alarms yet. To test this I actually hung it in the tool shed and piped the exhaust from a running generator into the shed and after about 15 minutes it would alarm, turn on the backlight and display the detected CO level. So I'm REALLY sure that it REALLY works to alert me to unsafe CO levels (although I don't have another device to compare to the accuracy of the CO reading displayed). I turned off the generator and placed a fan in the doors to ventilate the shed and it restarted once the levels got back to safe levels. Very happy with it so far!
π° Govee Water Detectors, Adjustable 100dB Audio Alarm Sensor, Highly Sensitive Leak and Drip Alert, Ideal for Kitchen Bathroom Basement (Battery Included)
9 Review
Xiaomi Mi Smart Sensor Set
45 Review
Aqara Water Leak Sensor: Wireless Mini Flood Detector for Alarm System & Smart Home Automation - Works with IFTTT
31 Review
Wireless Aqara Water Leak Sensor white for other countries
31 Review
π§οΈ Premium Quality Disposable Rain Ponchos for Adults / Kids (6 Pack) - 50% Thicker Emergency Ponchos for Ultimate Waterproof Protection
8 Review
π² Augason Farms Variety Pail Emergency Food Supply (Lunch and Dinner) - 4-Gallon Pail
8 Review
π½οΈ S.O.S. Rations Emergency 3600 Calorie Food Bar (Cinnamon & Coconut, 2 Pack)
8 Review
Lingito Rain Poncho: Buy 5, 10, or π§οΈ 15 Packs - Disposable Emergency Rain Ponchos for Ultimate Protection
8 Review