This is a mesh room you can use the #fyisewersystem. The #fyisewersystem lets you pick and choose several different sewer, bunker, tunnel, underground, etc pieces and link them together with several different styles of tunnels, to create your own unique build.
We recommend use with [FYI] Mesh Sewer Tunnel System S3, [FYI] Mesh Sewer Tunnel System S4, and later sewer tunnel kits.
Don't be confused by the name, these are modeled after large underground sewer systems, but you can use them for bunkers, fallout shelters, underground tunnel systems, military, etc. It's all up to your imagination with what you can do with these builder's kits.
This room is roughly 16m x 16m, and is only 5 land impact. Yes, that's right, this entire room is only 5 land impact!