USB Voltmeter ammeter voltag diff rence: have bluetooth board, do support APP. Because firware is constantly updated, Please refer to the products actually received. When using to detect the charger, it is necessary to turn on the CC drop down. When using to detect the charging process of mobile phone, it is necessary to turn off the CC drop down. The switch ON the product is the power supply switch for the system. When in use, set it to ON. If the voltage is less than 3.5v, use Micro-to supply power independently and set the switch to OFF. When TC66 USES the double-headed Typec line for the decoy triggering operation, only one side can be used. If it is not bright, please flip the interface. When you can't connect to the computer host computer or APP to save the measurement data in real time, you can use the offline storage function, you can temporarily store the measured voltage and current data in the tester storage unit, and then use the computer host computer and APP to generate the measurement data. Colour:black Material:plastic Package Contents: 1 x Type-C PD Trigger Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.