Check the listing for details. Mini Blue Volt Meter Bright Display Measures 2.5-30 V 2 Wires. Condition: New. Listed at 14.34 USD. Miniature voltmeter (23x11 mm) with blue LED display. It is capable of displaying continuous voltages from 2.5 to 30 volts using only 2 wires, in fact it uses the voltage to be read to power itself. Digit height: approximately 8 mm, precision: up to 10 volts 0.01 volts – over 10 volts 0.1 volts, working temperature: from -10°C to +65°C. Red wire: positive, black wire: negative. We ship all products within 24/48 hours with i best national couriers: Poste Italiane/SDA, BRT, DHL, UPS (national, European and international rapid), DHL, UPS And DPD (for international shipments). Do you need help before or after the purchase? Write to us WhatsApp al +39 051 6641440 to receive immediate assistance from a qualified technician. No call center, you speak directly to us. Your opinion is everything to.