This 56cm French Bertin frame on ebay has been customized by crunch--tightened the head angle so to speak. But, if you like interesting braze-ons for the 1950s, this one has several. The little double cable pulley on the right side of the bb I find particularly interesting as I am not a collector of 50s bicycles and haven't had the personal experience of using the double cable Simplex 543 derailleur. Lou Deeter, Orlando FL