Jims book says this chip is from Pittman and is R-7. The seller is therefore incorrect when he states "only 2 are known" but R-7 is "Very Rare" on the Rarity Scale which is pretty rare so, in the spirit of The Senate Hearings on Judge Alito, we can argue that he is both right and wrong.......maybe, I think, depending on who is asking the question. Heck I can't figure these things out anymore......