The letters are individual stickers on an adhesive strip, so wet the surface with glass cleaner (don't dry off the cleaner), press the letters (with outer strip still on) onto the surface (use a level to make sure it's level) and then peel off the outer strip. It's like putting decals/stickers on an automobile.
Die Cut Glass Window Decal : Fire Extinguisher Part #:LB-1949 1.5" x 15" Die-Cut Vinyl with Back Adhesive Verified PurchaseGood
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