Feature:1. The USB expansion board is very convenient to operate for novices and has stable performance.2. With excellent production process, the expansion board is not easy to solder when use it.3. The USB expansion board can compatible with multiple USB models, which is very useful.4. To solve the problem of insufficient USB ports, the USB interface changes from one to four in an instant, and it is also suitable for Raspberry Pi 3B/3B+, etc.5. Made of PCB, the expansion board is very durable after long time use without worrying.Specification:Item Type: USB Expansion Board ModuleMaterial: PCBWorking Voltage: DC 5VPurpose: To solve the problem of insufficient USB ports, the USB interface changes from one to four in an instant, and it is also suitable for Raspberry Pi 3B/3B+, etc..Package List:1 x USB Expansion Board Module1 x USB Cable1 x Two-in-One InterfaceNote:The USB to TTL serial port function can be used to debug for Raspberry Pi through the serial port, and the driver needs to be installed before use