Axia Alloys 17" Wide Panoramic Rearview Mirror - 1.5" Mounts These mirrors are only convex in the horizontal direction so that your surroundings appear exactly where they are in relation to your vehicle. Competitors mirrors that are more drastically convex in the horizontal and vertical directions and can make objects appear much further away than they really are. Hasadjustable mounting ball tension so that it can be tightened up for demanding off-road environments. This is the post / clamp mount. This mirror is supplied with the clamp adapte so you can mount it with any size clamp if you prefer