The easiest way to tell C-Record Deltas from Croce d'Aune Deltas is to look at the back. Records are completely enclosed. Croce's are not. Check eBay. There is almost always several sets of each up for sale, so you can look at the pics and get a better idea what I mean.
As for 3.5mm allen wrenches, Bondhus (sp?) makes 'em and I think you can order them form them on-line. Or you can go to Harbor Frieght. Last time I looked, they had a fairly cheap allen wrench set that included a 3.5mm. Either way is a heck of a lot cheaper than buying a Campy one.
Deltas are the Rolexes of brakes in terms of appearance: some people love the look; some people think they are garrish; everyone thinks they are expensive.
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