Use four at the same time. Support U disk hard disk printer and other devices. High-speed transmission. Supports plug-and-play and hot-plug capabilities for hubs and peripherals. Port current overload detection and protection function. No need to install any drivers. The size is purely manual measurement, there will inevitably be an error of 1-3 cm, please refer to the actual product. Due to shooting lighting and the difference of each monitor. There will be different degrees of color difference. The actual product shall prevail.