How much does this cost to the nearest dollar?

eufy Security, Entry Sensor, Detects Opened and Closed Doors or Windows, Sends Alerts, Triggers Siren, 2-Year Battery Life, Indoor-use Only, Requires HomeBase, Optional 24/7 Protection Service
2-year Battery Life One battery provides 800 days of monitoring. For Doors And Windows Compact and versatile design fits onto any door or window frame. Requires eufy Security HomeBase. Siren Enable or disable siren protection, which triggers a siren on HomeBase, and sends an alert to your smartphone when forced entry is detected. Optional 24/7 Protection Service New optional 24/7 professional monitoring service is now available for 24/7 emergency police, fire and medical response when your alarm system is triggered. What's Included Entry Sensor,

Price is $30.00
Price: $29.99