Description: 1.Double USB port and ciga lighter can be used with USB to support charging of multiple electronic products 2.Blue INDICATOR light with LED and blue LED digital display for voltage meter 3.Resistance to high current, high temperature and wear resistance 4.With waterproof cover, it can be covered with rubber cover to prevent dust and water if not used 5.The connection has positive and negative polarity anti-protection, so the connection will not burn out.erminals Material: Nylon+ABS Input: DC 12V-24V USB Socket Output: DC 5V / 4.2A Power Outlet: DC 12V Voltmeter Display Range: 0 - 24V Cautions: 1-Check maximum voltage on devices to charged in advance. 2-Always cover outlets when noy in use to aviod dust and water entering. 3-This product is for 12/24V vehicles only. 4-Only use on voltage specificed. 5-Do not operate this device while driving.