The decimal point is shifted automatically. If the voltage is less than 10 V, the number of digits displayed on the voltmeter will be 0.01; If the voltage is higher than 1 , the number of digits displayed on the voltmeter will be 0.1 and it will automatically. Features - Color: Black. - Size: 4.00X1.00X1.30cm/1.57X0.39X0.51 inch. - Material: Plastic. - Great mini digital DC voltmeter with new features: waterproof, and drop-proof. - Reverse Polarity Protection: The meter won't burn out if reverse polarity is applied, but the screen will display nothing. - Can be calibrated. The screw on the back is used to calibrate the reading. - Adopts precision production to the stable characteristics and high reliability. - Professional and practical design with beautiful appearance, easy to carry and use. Specification - Detection voltage: . 3 . - Working : <30mA. - Display: 0.28 inch . - Measuring rate: >=200 mS / times. - Measurement accuracy: 3%. - The maximum working voltage: 30 V. - Minimum working voltage: 3.5V. - Operating : -10-65 degree centigrade. Package list: 3 x Voltmeters