Iztoss 12-24V Blue Voltmeter Cigarette Lighter Dual USB Adapter Charger with switch 4 hole aluminum Panel plate For truck Boat marine trailer Four Hole aluminum Panel Base.the panel size is:90x90mm/3.54x3.54",driling hole size:65mmx65mm(2.56"x2.56"),Material: Aluminum Small size and excellent performance.Easy to install, convenient to use.Widely used for car, truck, motorcycle, for ATV and boat, etc. The parts are CE and Rohs approved . Installation requires drilling the stock dash for screws to mount the aluminum plates and cutting out the dash for the sockets to fit in place 1 Illuminated red waterproof on-off 3pins switches and 3.1A USB,12V/24V voltmeter,cigarette charger plug(can not used to smoke) included.panel is pre-wired and 4 screws and 2 Heat Shrink Wire Connector included for installation