Samsung Android Official Firmwares

Under normal state we do not have to use flash box to flash a Android device. This is because the boot loader of the android device can communicate via USB. Therefore if the boot loader is fine you could flash your Android device without using a special hardware like a Flash Box.

If yor device is a SAMSUNG you can download your official Android  ROMs from http://www.sammobile.com. Ones the ROM  has been downloaded, you could use Odin a software that use to flash SAMSUNG android devices to flash your Android device.