You are buying a REFLECTIVE MAGNETIC that is 7.5" tall. 

These offer extra safety at night, as they light up when headlights hit them. (Like the picture shows in low light conditions)

You can't compare these to any other. 

These are for long term outdoor use.

Made from sign grade .30 thick magnetic sheeting.

 These need to be put on a flat surface so there are no air pockets created. For best results apply magnets when they are 60 degrees or better. The surface needs to be clean. These need to be removed every month to clean the road grime off that may build up. Use a solution of soap and water to clean them and the surface they are to be placed. Do not trust them in car washes.