Dè a tha an sloinneadh Dall rivet a 'ciallachadh?

Ceann leum seamrag dall: leis nach bi an t-seamrag a’ pasgadh ceann na h-ingne, bheir e air ceann leum an t-seamrag.

https://www.yukerivet.com/news/the-core-of-the-blind-rivet-is-not-completely-pulled-out-what-is-the-reason-for-the-fracture/