These backs are wired to the steel hut and a steel post is driven in the center to keep the hut from flying in the wind. Each sow in the pen has a bedded hut available in the pen before farrowing. I suggest putting quite a few extra huts until you understand where a sow would prefer to farrow. They definitely won't farrow where an older litter was farrowed. And in hot weather they prefer to farrow in the coolest spot in the paddock.
Gilts are notorious for all farrowing under the only tree in a pen.
That's a sure disaster waiting to happen. Remember we have to help Mother Nature. We have to outsmart the pig. Circle huts with water and feed in middle would be ideal except for logistics of getting water and feed there. If your suited to pasture farrowing you will pick up these little tricks in nothing flat.