4pcs Mini V2.1 ELM327 OBD2 Bluetooth Interface Car Auto Bluetooth OBD II ELM 327 Diagnostic Scanner Tool So you only need two

So you only need two units for a simple conversion can know whether the temperature of the watch and APP display the same temperature

DIY style charger

Without the trouble of tangled wires

Compatible Device

support real-time video

4pcs Mini V2.1 ELM327 OBD2 Bluetooth Interface Car Auto Bluetooth OBD II ELM 327 Diagnostic Scanner Tool So you only need twoProduct Features: Support Bluetooth output protocol, ELM327 Bluetooth diagnostic, range: 1 10m. High quality wireless scan tool, support all OBD2 protocols, work with all OBD2 compliant vehicles. Enable to read diagnostic trouble codes, small Bluetooth interface with a 16 pin socket. Support different kinds of devices to use this scan tool: Android system phones, Symbian system phones, Windows XP and WIN7 32bite computers. Read diagnostic trouble