In the 'Allocation unit size' drop-down menu, use the default selection.However, if you think about using the device on a Linux machine, FAT32 is the best option, even though you will be limited to 4GB file sizes. Quick tip: If you plan to use the removable storage on Windows 10 as well as on macOS systems, you may want to select the exFAT option for compatibility. Use the 'File system' drop-down menu and select the NTFS option. Under the 'Devices and drives' section, right-click the flash drive and select the Format option. To format a USB flash drive using File Explorer on Windows 10, use these steps: How to format USB flash drive with File Explorer
