Review on Smart WiFi Door and Window Sensors - White, No Hub Needed, Wireless Design, Instant Alerts, 2.4 GHz Wi-Fi Required, Alexa and Google Assistant Compatible, Home Security by John Chembola

Easy integration with Alexa and easy to install. Pros: Integration into my smart home was very easy. We need a sensor so Alexa can tell if the door is open or closed. I have young children and need extra help watching the door, especially since the youngest knows how to open the door. Does as advertised, a little behind the ad but works. The downside is that it's a lot more than I thought it would be. He runs on two AAAs, so far so good. So if you're expecting a small door alarm, this isn't it. But I can't complain positively about the price!