Originally Posted by tony colegrave

No factory-made #99 ever existed (neither did #91, come to that - an eBay invention by 'spanner 48'), and the Swallow-type '99' saddle on eBay at present is almost certainly a TB 90, 'butchered' after it left the factory. The other '99', currently on offer (again), is a rather decrepit TB 59 which has lost it's all-important seat-pin clip (if you want to ride the thing, that is). The numbers that are often stamped into the alloy girder rails generally appear to have no correlation to the saddles on which they appear - 4/8, 5/9 and, especially, 9/0 seem to be the most commonly encountered 'matches'.