10 PCS 2.5V-30V Mini 0.28 inch LED Digital Voltmeter Voltage Tester Meter Displa

Red: 2.5V - 30V. Yellow: 2.4V - 30V. Green: 2.5V - 30V. It can be used for 5V, 9V, 12V, 24V Circuit. Installation hole: 23 × 10 mm Color.

eBay