[Upgraded Design] Features an ON/OFF contact button; the 12V/24V dual-port USB car charger allows independent control of USB charging ports and the LED voltmeter, reducing the need to repeatedly plug and unplug charging cables and helping preserve battery health. [Dual USB Car Charger] Two USB ports deliver up to 2.4A per port (total 4.8A), enabling fast simultaneous charging of two devices. Built-in smart charging IC automatically detects connected devices’ power requirements and delivers optimal charging speed while protecting against overcurrent and overheating. [Digital LED Display] Integrated blue LED voltmeter monitors vehicle battery voltage in real time, helping users assess battery condition while driving and identify potential voltage issues. [Waterproof Design] Equipped with a rubber USB cap for dust and water resistance, enhancing protection of internal circuitry and extending product lifespan. Compatible with most 12V–24V vehicles, including cars, trucks, SUVs, RVs, boats, motorcycles, ATVs, golf carts, and more. [Easy Installation] Designed to fit standard dash panel openings (~3 cm diameter). Install by connecting the positive wire to a fused power source and the negative wire to the vehicle’s ground. Secure the unit in place with included hardware. Compatible with all USB-powered devices, including iPhone 11/8/8 Plus/X/7/6S, Samsung Galaxy S10/S9/S9+/S8/S8+/S7, iPad, Android tablets, power banks, and smartwatches. Color: Black Material: Copper + ABS Package Includes: 1 x USB car charger 1 x Connecting wire with fuse (60 cm length; port color may vary) Notes: 1. The voltmeter display activates only when the unit is powered. 2. For automotive use, connect to a fused power source.