
Samsung Galaxy A3
Every official firmware build for SM-A300M, newest first: one row per build with all regions (CSC) that received it.
Each firmware build has its own page at https://samfirm.shop/build/{PDA}, where {PDA} is the build number from the list above. Example: https://samfirm.shop/build/A300MUBS1BRK5
Specifications of SM-A300, a regional variant of the same device. Chipset and SIM lines are left out: they can differ by region.
• Network connectivity enhancement.
· Device stability improvements, bug fixes.
· New and / or enhanced features.
· Further improvements to performance.

SM-A300XU

SM-A307GT

SM-A305YN

SM-A310X

SM-A405S
You can find the firmware on the model: SM-A300M page.
Yes, all firmware files for SM-A300M are 100% official, original, and obtained directly from Samsung servers.
To flash SM-A300M, you need to download the appropriate firmware, put your device into Download Mode, and use the Odin tool to load the BL, AP, CP, and CSC files.
Downgrading is only possible if the bootloader version (binary bit) of the old firmware matches the current one. Always check the binary version before flashing SM-A300M.