This piece was found in a junk store among a sea of clear CD 128's.

When I saw it, I thought to my self, I've never seen a CD 251 in a LYNCHBURG before. So, I purchased it for fun and have come to find out that it is listed as a $50-$75 insulator. (In better condition of course.) I have no idea why it's priced this high. Maybe it was not produced in high quantities, but that's just a guess. Anyone have a clue as to why it's priced so high?

It's damaged, but it made my day finding a rare-ish/oddball insulator amongst the junk.