Amazon has Kidde Carbon Monoxide Detector Battery Powered on sale for $17.76 . Shipping is free with Prime or on order $25+
- CO detector with alert modes & LED lights that pulse for power, CO detection, & low battery
- Sophisticated electronic components to protect you & your family from the dangers of carbon monoxide, 85 decibel alarm alerts of fire
- Protects during a power failure – operates on 2-AA batteries, included with pack
- Whole home family protection – place 1 carbon monoxide detector on each level of your home & in your bedroom to protect from poisonous gases
- UL Certified, 10-year limited warranty
Amazon offers free shipping with $25+ orders or get free 1 day shipping on all orders with a free trial of Amazon Prime. A prime trial is also free with Amazon Family (which also gets you up to 20% off diapers among other benefits) or Amazon Student. EBT/Medicaid Cardholders can save on Prime Membership here.