I was in an attic recently that had a ratchet style crank that was attached to a plate screwed into the attic floor and then attached to a crow bar between two eye bolts that went to the exterior wall (which was plumb by the way). I also found three other similar setups like this in another part of the attic attached to the roof sheathing and then also attached to the ridge. This was installed in a prefab home put together in 1994. I personally haven’t seen anything like this yet and wondered if someone could shed some light on what the purpose of these straps are. My clients concern would be whether or not to differ this out to a structural engineer for further assessment. See attached pictures.