Have you ever gone to start up the grill to cook some delicious barbeque and then realized your propane tank is out of gas? Never run out of propane again! With the help of the Smart Propane Tank Scale from Flame King. Advanced smart technology works to help you track and measure the gas levels of your tank. It works with Bluetooth and our free app so you can monitor weight on your mobile device or phone. Download our free app on either iTunes or Google and easily connect your scale to your mobile phone or device. It’s super convenient and easy to use! Now you’ll always know when your tank needs to be refilled! PRODUCT FEATURES: Bluetooth Connectivity Measures: 12 x 2. 5 inches Free Smart Scale App Compatible with 20, 30 and 40 lb. Cylinders 2-AA Batteries (not included)TRACK PROPANE LEVELS WITH YOUR PHONE Monitoring and tracking the gas levels in your propane tank is super easy with smart technology. Our wireless scale connects to your phone using Bluetooth connectivity and our free smart scale app. With the app you can weigh and measure gas level percentages. The app stores measurements with a date stamp directly in the app so you don’t have to remember and it keeps track of the last time you used it. We’ve also added a bonus feature that helps you monitor your long-term propane consumption. HOW IT WORKS To get started download our free app. You get free readings for 20 lb. tanks and a free trial for 30lb and 40 lb. tanks followed by an in-app purchase of $1. 99. Our app will ensure your device is ready to go, so no need to worry about your Bluetooth device settings. Turn on the Flame King Smart Propane Scale using the switch at the bottom then place your propane tank on the scale and tap “connect scale” in the app. We recommend keeping the scale near or better yet, under your tank. To save the battery life, make sure to turn the scale power off after each use.