Lowe's offers the Halo Ac Hardwired Photoelectric Sensor Combination Smoke and Carbon Monoxide Detector for $89 with free shipping. That's the lowest price we could find by $11. It works with home assistants like Iris, SmartThings, and Alexa, and features six types of safety sensors that detect carbon monoxide, fast-moving fires, slow, smoldering fires, and reduce false alarms.