I have a couple of brand new 1/2" 5C collets, in the wrappers and never been used, but I already have an imperial set. If anyone would like to swap them on a 1 for 1 basis for a metric size (I don't have many of those) drop me an e-mail. Or if anyone wants to swap them for anything else interesting let me know. I'm never likely to use three 1/2" collets at the same time!. They are from J&L and are "Interstate" brand.