Can I screw in numbers to my concrete letterbox?

We do not suggest screwing numbers into your concrete letterbox, as the exposure to weather elements could cause damage, as well as the potential for the concrete to crack due to the vibrations during installation. We suggest you screw your numbers into your fence, and instead use Stick on House Numbers or a Custom House Sign for your concrete letterbox. Our stick on house numbers range have been specifically designed for our concrete letterboxes to make installation a breeze.