Kit-Bash! Update 2.1+ is a release file of the Minecraft resource pack Kit-Bash! - Immersive Railroading Pack (LEGACY/NO LONGER SUPPORTED), made for Minecraft 1.14.4, 1.16.5, 1.10.2, 1.15.2, 1.11.2, 1.12.2, 1.13.2. It was published on August 28, 2021 and is 310.9 MB in size. For the full description, screenshots and every other version, visit the Kit-Bash! - Immersive Railroading Pack (LEGACY/NO LONGER SUPPORTED) resource pack page.
How to install: Put the .zip into .minecraft/resourcepacks (do not extract it) and enable it under Options → Resource Packs.