It says SC on the connectors in the picture, so one would assume that they are SC connectors...
Woah! Good eye! I was about to reply and ask where you saw that, then I zoomed in. I completely missed that and I had those connectors in my hands. Bravo, sir!
Edit: They seem to be Corning Anaerobic Connector, SC, 62.5 µm multimode (OM1) and the boxes you ordered are for 50/125µm or 2.5/125µm. I don't know if that matters, but it may be why they don't fit properly. Well, looking at the frequently bought together, they list a 62.5/125µm patch cable so maybe not... Unless 2.5/125µm is a typo and it should be 62.5/125µm.
You've got me on this one: how could you tell that they were 62.5/125 cables and not 50/125 or 9/125 (I only learned about these sizes two minutes ago after seeing your post)?
You're right, though, the product description says 50 and everyone seems to be buying 62.5 cables to go with it. I'm not sure why that is...