NMMLib-1.0.2.1.jar is a release file of the Minecraft mod NoMansLib, made for Minecraft 1.12. It was published on June 14, 2017 and is 0.8 MB in size. For the full description, screenshots and every other version, visit the NoMansLib mod page.
How to install: Put the .jar into the mods folder (.minecraft/mods) and start Minecraft with the matching mod loader profile.
