Mercian 520 Audax frame built with Reynolds 725. Top tube length 540 top tube. Vertical rear dropouts. 71 deg head angle and 74 deg seat angle , 425mm chain stays with clearance for 28mm tyres and mudguards with 47/57mm brakes . 1″ A-Head down tube lever bosses and chain stay stop with a nylon tunnel under shell for the gear cables. 4 point rear rack brazing . Sprayed Black enamel with white head tube and finishing details. Complete with a Tange sealed bearing alloy headset.