How to change the 4 gb usb flash drive of Kingston to 2 GB

Since a PC system is out, there is no optical drive, and no dos boot menu or the like, I want to use the USB flash drive in my hand to guide the restoration system, so I found a tool for making USB boot, -- USB boot, USB flash drive 4 GB, prompting that it must be used as the HDD mode. After the hard drive is finished, the 4 GB disk is changed to 2 GB. Formatting & related repair tools are ineffective, baidu and Google didn't even have any words related to them. They thought they had put out a chip and thought about a 2G disk. They just put out the remaining 2g, Hoho... I have to find Js for a new version, so it's always 2 GB. suddenly I want to open it in the disk manager to see how it is displayed. Open the current screen:

I was in an extreme mood, ^, prompting me that I didn't assign the assignment. Now I am assigning the assignment, but right-click the assignment, and I cannot use it for the rest, and I am depressed. Open IE and find it, find a collection of USB flash drives, go down to the desktop, find the uformat tool, and test "0 parameter RESET ", -- in fact, it is to use 0 to reset the MBR & dbr of the u disk to process the U disk in raw format, and then format it to fix the total capacity.