Have you been looking at a clamp on style bar end mirror but can’t figure out how to fit the mirror to your Triumph Bonneville, Thruxton, Scrambler, America or Speedmaster? British Customs has developed a clamp on mirror adapter that will work with a Triumph clamp on mirror or any clamp-on mirror that fits onto a 21.85 mm surface. The adapter is machined from 6061 aluminum and black anodized to prevent oxidation, and is a direct replacement of the factory bar end, fastened on using a supplied M5 bolt.