It seemed only right that an old French bike should have a French saddle. This one,from Gilles Berthoud is a masterpiece of Gallic engineering design. My only complaint is that it looks a little synthetic from the rear end.
Tension can be adjusted with a simple allen key at the front end.Rails are chro-mo and that circular gizmo is for rail tension adjustment.
Rather than punched in rivets,a la Brooks,the GB has these screwed in fasteners. The front one is stamped with date of manufacture and serial number.