Fast & Easy to use: just place them magnetically on your steel whiteboard or any steel surface indoors or out.* Use a strip of tape for alignment. Peel up tape when done. They will cling tight and "lock on" magnetically to the steel surface and become very difficult to slide, but can be lifted off and repositioned easily. Colors are fade-resistant in the sun. Characters are Helvetica type style, full width (even the large letters) for easy reading from a distance, Reuse them over and over for years.
* Except some grades of stainless steel.
Caution: magnetic die-cut characters become brittle and may fracture when flexed or handled in below freezing temperatures but stay functional if left undisturbed.