Originally Posted by Rob-F
I use both Leitz and Voigtlander adapters without problems. I tried the cheap Chinese ones. They were no good, and when I asked to return them, the seller refunded my money without asking that they be returned: They weren't worth the price of the return shipping to him! So that ought to tell you something . . .
But the Rayqual adapters are great, above all the black ones.