It's a container that you can walk into and build something in.

size : 184 x 68 x 60m (23 x 9 x 15 (by 4m foundation))

Inside room size : 104 x 56 x 48 m ( 13 x 7 x 12 (by 4m foundation))

"Conveyor Belt lv.1 (Road, Tunnel System)" [addon] : https://satisfactory-calculator.com/blueprints/index/details/id/2297/name/Conveyor+Belt+lv.1+%28tracks+system%29

"the Computer" : https://satisfactory-calculator.com/megaprints/index/details/id/1398/name/The+Computer

reddit post https://www.reddit.com/r/SatisfactoryGame/comments/10dxysx/have_you_ever_been_inside_a_container/?utm_source=share&utm_medium=web2x&context=3