Feature: Reverse does not burn, the number does not shake. Digital tube: 36 x 14 x 13mm (L x W x H). Board: 35 x 16mm. Power supply: 7-30V, high brightness LED digital tube. Color: red, blue, green, yellow (optional). Voltage: Range: 0-33V, error +-0.02V. R ange: 0-200V, error +-0.1V. Power supply 7-30V. Two r anges are available. Temperature: -50 ° C ~ 125 ° C, NTC probe, extension line 1 m, waterproof. Accuracy 0.0625, no calibration required. Time: 24-hour system, clock chip accuracy of 15ppm, with power off memory function, accurate time. 4 display modes: 1: Display time only 2: Display temperature only 3: Display voltage only 4: Time temperature voltage is alternately displayed. Note: 1. The difference between 33v and 200v is that the maximum measurement voltage is different. Car battery 12v can select 33v, and electric vehicle can select 200v. 2. Three-in-one table temperature sensor line defaults 1 meter, can not be extended, will affect the accuracy of time after extension, please think twice. Key setting: Button 1: Short press to select the clock, second, voltage, temperature display mode; Press and hold to display ALL, enter the time---voltage---temperature tracking mode, with an interval of 5 seconds. Press the button again to exit the mode. Button 2: Short press to adjust time, minute (flashing), and press one button to adjust. Press button 2 again to exit the adjustment mode. Remarks: Adjust “minutes”, the clock will stop after exiting, and press the button to start walking. Package includes: 1 x Voltmeter