With the history of Fotodiox tripod adapters being so weak, and on a recommendation last year, I upgraded to a CIECIO7 FD/NEX tripod adapter for the NEX-7 and after seeing how brutally strong it was, got another NEX-7 set up the same way…more expensive than Fotodiox but we get what we pay for and the CIECIO7 adapters are definitely high quality / hold a lot of weight. Tossed the Fotodiox tripod adapter in a parts drawer or something last year and forgot about it. Fast forward 10 months and in getting ready to experiment with some macro photography this summer, I pulled out a Canon FD 50 Extension Tube I had. But when I tried to mount it on the CIECIO7 adapter, discovered that there’s apparently just enough difference in the tolerances of the twist lock flanges of the Extension Tube (compared to my entire inventory of Canon FD lenses) that they won’t allow the corresponding flanges on the CIECIO7 adapter to slide under them, therefore the tube can’t rotate and lock in place. Dug around some more and finally located adapter I still had after all, and was surprised to find that the Extension Tube fit OK…corresponding twist lock flanges on the Fotodiox are just enough smaller / thinner to let the tube rotate on. But no way would I trust the weak failure prone Fotodiox tripod adapter to hold my lenses and remembering a thread on the NEX Forum from last year…I followed that suggestion, modifying / making the Fotodiox adapter much, much stronger by drilling / tapping for large 6-32” stainless steel screws…reinstalled the foot and large screws covered in Epoxy, all done in less than an hour. The weakness of the ridiculously small Fotodiox screws is obvious in the photo, compared to the strong stainless 6-32" screws I used for the modification. (got some lint on the adapter that I’ll rub / sand off after the epoxy cures solid). I'll just leave the adapter permanently installed on the Extension Tube.