1. Regarding the U-disk heating phenomenon Heating is normal. When the U-disk is powered on, it performs data transfer and reading, causing the electronic components to emit heat. Metal has good thermal conductivity and heat dissipation, so it is normal for metal U-disks to heat up, and not a quality issue. 2. Regarding the U-disk read and write speed The read and write speed is related to the computer's USB interface, the size of the copied file, the U-disk format, and the computer's operating system. The read and write speed will vary depending on usage conditions, which is a normal phenomenon when using a U-disk. * Mobile solid-state products must use USB3.0 or higher interface to achieve the official speed. If the measured speed is around 40MB/s, it means that the USB2.0 interface is connected, and be careful when using it. 3. Regarding copying a folder being slower than copying a single file When copying a single file, the system only needs to create one index. When copying a large number of fragmented folders, each file must be indexed, so it takes a relatively long time. And if multiple tasks are performed at the same time, it will also increase the load on the computer, leading to overload and slowing down of the channels. 4. Instructions for copying files larger than 4GB To be more compatible with the operating system, the U-disk's default file system is FAT32, and the maximum single file is 4GB. If you need to store a single file exceeding 4GB, it is recommended to restore the file system as follows: 1. Connect the storage product to the computer 2. Right-click on the partition and select Format 3. Select exFAT format in the file system option 4. Click Start to complete