ITEM NAME:Mini DC 3-30V Blue LED Panel Voltage Meter 3-Digital Self-Powered Voltmeter #gib Store Home Promotion Hot Item Add to Fav.The maximum input: 30V. Connection is simple, just need to pick up two lines, a joint reverse protection, and then do not burn. Display mode: three 0.36 LED digital tube. Permissible error: 1% (+ / -1 word).