Warning: Support cell phone with Bluetooth 4.0 or above . DO NOT support Cellphone with Bluetooth lower than 4.0. Product displays by cellphone. During driving, please be careful when viewing tire pressure and temperature in cellphone. If tire pressure accelerates down or up continuously, please parking and check if there's any problem with the tire. This product can read tire pressure and temperature, but it cannot avoid sudden accident caused by tire.It's important to use. Tire with high quality. Slightly tire leakage makes tire pressure decreases over time is normal. It has nothing to do with this product installation. Description: Dynamically monitor tire pressure on 4 wheels at same time, prevent damage from flat tire, Improve fuel efficiency, prolong tire life span, ensure driving safety. It was designed as a direct tire pressure monitoring system, installing pressure and temperature sensor on the tire, then displaying the real-time data on phone (Android , IOS, IPad) through Bluetooth connection, During travel, tire pressure and temperature displayed in real time and send alert when statistics' abnormal. For your safety. TPMS supports both Android and iOS, requires Bluetooth 4.0 or above. APP Descriptipn: Compatible Operating System:TMPS Support Both Android And IOS, Requires Bluetooth 4.0 or above APP Installation: Option 1: Scan QR code on card, then download and install; Option 2: Search BEL TPMS in APP Store or Google play Store, then download and install. Pairing instructions: Recommend use method: bind by scanning code Open the APP. Pleaase scan the QR code card which with words"one-clicking binding"or complete the binding by scan the corresponding sensor ID code. Installation and pariring Open APP. Please follow the sensor's mark and install sensor on correspoding tire until get each sensor date The installation is complete. Note: If the date of sensor cant be get , pls re-install the sensor. (please install slowly to make the air pressure fully contact the sensor) Suitable for cars, not suitable for trucks. Package Included: 4 x Externer Sensor 4 x Screw 1 x Wrench 1 x User Manual 1 x Sensor ID Do drop