A wireless door/window sensor that attaches to entry points and sends real‑time open/close status to your phone via the eWeLink app without needing an additional hub. It delivers instant alerts on activity, can be linked to smart cameras for visual confirmation, and stores activity logs for up to 3 months in the app. Easy tool‑free installation with 3M adhesive, works on 2.4 GHz Wi‑Fi, and includes low battery alerts for reliable home security.