Yolink Smart Home Starter Kit: Water Sensor 4-Pack And Hub Kit, And Email Alert. Product Features Easy to install. Scan, Plug and Play. Full installation and setup in less than 10 minutes Protected and informed, with Realtime phone app notifications, emails, SMS messages and automations (turn on optional sirens, smart plugs..) FAIL/SAFE: Patented technology! Pair your leak sensors to battery powered valve controllers and/or sirens. No internet, no WiFi, power outage no worries! Latest Wireless Technology LoRa: low-power consumption (5+ year battery life) and "Longest Range, by Far!" (1/4 mile, open air) Whole house smart home solution: Your YoLink leak detection system is part of a complete product line, including smart wireless automatic water shut-off and a full smart home solution, including security, locks, plugs switches, temperature, humidity, and smoke/CO sensors, and more Requirements ? Android or iOS smartphone, wired ethernet port or WiFi connection. App is always free, with 5 free texts per device, plus 5, per month. Shipping: Shipping is complimentary within the lower 48 US States. We Do Not Ship to PO/APO Boxes, HI or Alaska We Do Not Ship Outside of the Continental US All items ship within 24-72 hours of Payment For large items that require Freight shipping a valid phone number is required to call and schedule your delivery Terms of Sale and Feedback: Feedback is extremely important to us and If you are satisfied with our transaction, please take a moment to leave Positive Feedback. YOUR Satisfaction is our #1 Priority! If there are any issues, PLEASE contact us BEFORE leaving a neutral or negative rating so that we may resolve any concerns. We PROMISE we can make you happy if you give us a fair chance. Returns / Concerns: All items qualify for returns within 14 - 30 days of receipt. Buyer is responsible for return shipping on any item that is not damaged Please be sure this is an item you want before making your purchase. Customer Satisfaction is our TOP priority! All items are IN STOCK at time of listing. Inventory changes constantly and it is impossible to maintain a perfectly accurate count of all items. Please do not penalize us if we have to issue you a refund! Thank You For Your Business!