These decals can be used on metal, paint, plastic, glass and almost any other smooth surface.  They are safe for screens, Laptops, Computers, Cars,  the back of a phone. They can be easily be fully removed if necessary.  

Decal has NO BACKGROUND - When applied you will just see the letters and graphic(s). What you apply it to will be the background.  If applying to a very dark surface, you may want to choose a light color for the decal such as lime.