[CR]Campy front der. Flat cage and no circlip?

I think my next bike will be mostly NR. I am starting to look into gathering parts, and was wondering about the significance of the quote with this front derailleur (Richard Sachs is the seller) "It has flat cage and no circlip".

http://ebay.com/<blah>

Richard gave me the info that this was part of a 70's consumer product safty commision improvement. But now curiosity is killing the cat (me), and I am trying to figure out what on earth would a circlip and a flat cage have to do with saftey. Which circlip anyway?

Thanks in advance, and rest assured that I will not hold anyone responsible if I get injured with this or a similar derailleur.

Thanks Dan Kasha Providence, RI See my bike at: http://members.cox.net/kasha.lists/peugeot/peugeot.html

PS Don't think I might not raise by bid (now too low) on that signed campy box!