Upgrade stickers are the ones that take you from 50 to 100 to ...U.S. Basic certificate- $1.00 (US); Additional upgrade stickers -$1.00 (US) per application, or one (1) SASE per each application. >
up to 300 QSOs.
Endorsements are the specialty stickers, like Lower 48, the DX
specials, and the Hot Dog.