Wide angle mirror glass has a vertical line in /4th of the mirror glass. The blind spot reduce area that neither the wing mirror nor the rear view mirror reflects. Before switching lanes, drivers usually have to turn their heads and look back over the shoulder to make sure the blind spot is clear. A blind spot mirror makes checking the blind spot more convenient and safer. Pass mot, replacement for most uk and ue driver side mirror glass, you can buy this mirror to upgrade your convex standard glass. Fitting instructions: (for self adhesive type mirror glass) thoroughly clean and dry surface to which replacement glass is to be fitted. Wemend you use clean water and dry with a soft cloth. Carefully remove any loose glass and dust off any small particles. Do not apply outdoors in damp or cold conditions. Do not remove any glass unnecessarily. Where the original glass is bonded to the door mirror assembly, this will provide a sound base onto which the new glass will adhere.