OEM Heated Non-Dimming Mirror glass with backing plate attached, clips directly on the motor Mount Diagonal Measure (Longest): 8 3/8 inch = 21.3 cm. Longest diagonal dimension provided is the longest size of the glass in any direction, normally longest top to opposite bottom corners measurement. Genuine Factory - Clips on Mirror Motor The longest diagonal dimension provided to help ordering proper fit. OEM Mirror Glass This mirror glass has Diagonal Measure (Longest): 8 3/8 inch = 21.3 cm Same year/make/model may come with different mirror shape or sizes depending on the markets they released in, options installed, or mirror may have been changed over the course of the life of the vehicle. Please compare actual picture and the longest diagonal dimension provided to your vehicle prior to order to make sure of ordering appropriate fit.