The HidrateSpark Steel 21oz Straw Lid has an LED smart sensor puck that glows to remind you when it’s time to drink and tracks your water intake by syncing via Bluetooth® to the free HidrateSpark App. It features a rechargeable battery and includes a charging cable. Customize the bottle by choosing between unique glow colors and exciting light patterns available within the App. This BPA-free, vacuum-insulated stainless-steel bottle is designed to keep beverages cold for up to 24 hours. The double-wall construction prevents condensation. Recommended to hand wash only. Do not submerge, wash or get the sensor wet. Do not use this product with hot liquids.