This maybe the only time one of these insulators have been offered, I,ve sold a few of the (030) a few years ago, however i,m offer, n only 1 of 2 i own... (045) CD 154 threaded skirt with which appears to be the C.N.R blott out..The C appears to be noticeable just left of the Diamond, while the N and R must be into the mould of the Diamond..This blot only appears on just the front skirt only..(one side only).Blot, I'm hav, n a hard time to photo, but it, s there... Account of the rarity my askin price is $75.00 plus shipp.n.