I came across this site while searching other things. What caught my eye was the "sex bolts". Apparently this is a "mating fastener". We have seen them as a bolt thru type connector for furniture. But they have a huge selection of this kind of fastener in various materials. As well as parts for jigs, etc.
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are six different PDF catalogs listed on this page.I am going to be looking these pages over carefully. I have a project coming up that will require large DECORATIVE fasteners. Maybe a nice shoulder bolt in stainless steel.....