Review on White Wireless Smart Door/Window Sensor (2-Pack) by Monoprice - Compatible with Alexa and Google Assistant, No Hub Required - from Stitch Collection by Ted Slaughter

Batteries included! Very good. Installation is quite easy (only works with 2.4GHz WiFi!), the kit includes 4 AAA batteries with 3M glue and 8 screws for sensors (depending on how you want to attach them). My only criticism of the 3M adhesive is that the cut out hole on the back is a little hard to see so I actually applied it upside down - I assume it's for tamper evident purposes. In any case, I'm only rating these 4 stars because the app's notifications seem questionable at times - in one instance, I received a notification that my door was open after an hour, even though I had checked the history beforehand, did the notification show the event? Seems to be a good product so far, the added benefit of being safer while I'm out of state!