https://smile.amazon.com/gp/product/B07JPL7W7N/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1
https://smile.amazon.com/gp/product/B004QJVU78/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1
The top one is super loud if the freezer gets unplugged
the bottom one tells you if you left the door open