Anti Clock wise rotation Tachometer Replica Smiths Dimension Details: Bezel = 3 1/4 " (85 mm) Body = 3 1/8  " (80 mm) Thread Size for cable  = M12 X 1  with mounting bracket and 12 v bulbs for illuminaion. should fit many vintage Triumphs BSA Norton Matchless Bikes (confirm fitment at your end before buying) SMBL80MM-ACW-CR