Samsung Galaxy LIGHT (SGH-T399N) Firmware Overview
The archive lists 4 official builds for the Samsung Galaxy LIGHT across 1 region (CSC). The newest one is T399NUVSAQA1, released February 15, 2017 with Android 4.4.2.
How to Flash SGH-T399N Firmware
Put the Samsung Galaxy LIGHT into Download Mode, load the BL, AP, CP and CSC files into Odin on a Windows PC and press Start. Pick a build with the same or a higher Bit than the one installed — a lower bootloader binary will be rejected.