O1.zip is a release file of the Minecraft resource pack SECR O1 class for Immersive Railroading, made for Minecraft 1.16.5, 1.12.2. It was published on January 9, 2022 and is 23.7 MB in size. For the full description, screenshots and every other version, visit the SECR O1 class for Immersive Railroading resource pack page.
How to install: Put the .zip into .minecraft/resourcepacks (do not extract it) and enable it under Options → Resource Packs.
