In this counterfeit detection video, our QC tech Ed shows us how he discovered that this group of parts were counterfeits.

Although they exhibited many clues, his initial indication was the re-tinned leads. Watch as he notices that the outside surface of the leads was sanded (see directional sanding marks), the parts were blacktopped/resurfaced, the bottom of the parts were sanded down and the band on the top indicating the mounting direction of the part had been re-applied.