Probably 21” Nervex on a Reynolds 531db tube set as a dual purpose machine for club use and a bit of racing typical of the era. The long wheel base gives extra comfort and space for mudguards and 27” wheels as well as sprints or 700c options. Full wrapover seatstays, curved seatstay bridge which doesn’t appear to be reinforced and a centrepull brake bridge. It looks from a glimpse of the chainstay bridge that it is curved too. The fork blades are typical of the date and have a nice Vagner model 12 crown with lozenge fraise top. Dropouts are Campagnolo with mudguard eyes.
The brazeons are under top tube pump pegs, brake cable guides and stops at 4pm on the off side, an under DT band-on shifter stop. The BB has a rear derailleur guide and there is a cable stop on the OS chainstay.
A high quality frame in desperate need of a good period refinish to show it at its best. Plenty of 60’s examples on the site from which to take guidance and produce a stunner!