1. Regarding the U-disk heating phenomenon Heating of the U-disk is a normal phenomenon. When the U-disk is powered on, it performs data transfer and reading, which results in the electronic components of the U-disk emitting heat. Since metal has good thermal conductivity and heat dissipation, it is normal for the metal U-disk to heat up, and it is not a quality problem. 2. Regarding the U-disk read and write speed The read and write speed of the U-disk 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 the 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 an 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 4 GB To be more compatible with the operating system, the U-disk's default file system is FAT32, and the maximum unit file is 4 GB. If you need to store a single file that exceeds 4 GB, it is recommended that you 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