Features: This 4 port USB car chargers features double 3 and double 3 ports, delivering fast charging speeds up to 4 times faster than standard chargers for simultaneous device charging, including smartphones and tablets, with built in voltmeter display for real time monitoring. Crafted from metal shell and ABS plastic, it offer superior heat dissipation, waterproof protect, and comprehensive safety features like overload, overvoltage, and short circuit protect for stable performances. Designed for car owners, truck drives , travelers, and marine enthusiasts seeking efficient and safe charging solution in various mobile environments. Ideal for use in cars, trucks, , boats, and motorcycles during travel, commutes, or outdoor adventures, providing versatile charging access with its wall mount design. Easy to install in minutes with simple polarity connection, this double QC3.0 accessory ensures durability and compatibility with 12 24V systems, making it essential for on the go charging needs. Specifications: Product name: Bus, , car chargers Input: DC12V-24V USB-A output: QC3.0 18W USB-B output: QC3.0 20W Output interfaces: TYPE-C Size: about 89x41mm/3.5x1.61inch Package Includes: 1x Car chargers note: 1.Please allow 1-2cm errors due to manual measurement, make sure that you do not mind before you order. 2.Due to the difference between different monitors, the picture may not reflect the actual color of the item.