The king of mirrors this 17 Inch billet panoramic rearview mirror offers the widest non distorted viewing angle of any mirror on the market. This mirror is very slightly curved ONLY in the horizontal direction so that you get a nice wide view of what is behind you without distortion. This is the SHORT ARM version. 1.5 inches mounting length. Axia alloys recommends that you use the 1.5 inch length arms on aftermarket cages where the mounting bar is far enough in front of you. Lifetime warranty on all Axia mirrors.