1Set DC Voltmeter Display 3-Wire DC 0-100V Voltage Tester 4 Colors Combined4371\n\n[Mini DC Voltmeters]Total 10PCS, 4 colors combined(2PCS Red/Yellow/Blue/Green/White); 0.28 inch LED Panel; small in size and light in weight; wire is made of 28awg gauge; install the hole: 23*10 mm \n[2 Connection Methods]3 wires are connected separately to measure voltage and power(Red yellow is both for pos, black is ); 3 wires are used as 2 wires, connected to measure voltage(Red and Yellow can be paired for pos, black is )\n[Features]Reverse polarity protection, voltmeter 't burn out if reverse polarity is applied; high ; low starting working voltage; fine adjustment function\n[Note]Max voltage with yellow and red connected is 40V.To measure 40V (up to 100V) the yellow wire is connected to a separate voltage source that is 40V or less\n\nColour:multicolor\nMaterial:led\n\nPackage Contents:\n10 x DC Voltmeter Display