There is currently less than 3 days left on my kickstarter for sci-fi battlefield. This bunker, the third, is provided completely free as a sample on what to expect.
https://www.kickstarter.com/projects/terrain4print/sci-fi-battlefield-st...
The bunker comes with metal reinforcements in two shapes, profiles and nuts. It also comes in old condition, damaged and ruin.
You can also support my work on MMF tribes:
https://www.myminifactory.com/users/terrain4print#/