v12.3.4 is a release file of the Minecraft mod Additional Enchanted Miner, made for Minecraft 1.12.2. It was published on March 19, 2020 and is 1.9 MB in size. For the full description, screenshots and every other version, visit the Additional Enchanted Miner mod page.
How to install: Put the .jar into the mods folder (.minecraft/mods) and start Minecraft with the matching mod loader profile.