Works with Apple Find My: Apple users can easily connect the tracker to the Find My app via Bluetooth, allowing global tracking of your belongings through the vast Apple device network. Water-Resistant with Rechargeable Battery: The SmartTrack Card has a rechargeable battery that lasts up to 1 year on a single charge. Its water-resistant design ensures durability, even in rainy conditions. Ultra-Loud 80dB Alarm: The SmartTrack Card's loud 80dB alarm ensures you can hear alerts, even in noisy environments. Compact and Lightweight: At just 2.6 millimeters thick and ultra-lightweight, it fits perfectly in your wallet, passport holder, laptop case, or folder. Shareable Location: The eufy Security app allows you to share the location of your items with friends and family.Free Left-Behind Alerts: The Find My app sends instant notifications when you leave an item behind. No subscription is needed.