Maidenhead grid squares are a popular way to divide up a geographic area for VHF/UHF activity and now more commonly via the FT8 digital mode. The FT8 Digital Mode Club sponsors the Worked US Grid Square Award for those operators who contact American stations in at least 25 grid squares.
You can chase additional certificates for working more grids at the 25, 50, 75, 100, 150, 200, 300, 400, 500, 600 and “all” level. The contiguous 48 US states take up 488 grids, so it appears the “US” here refers not to the DXCC entity US but rather the nation. So Hawaii and Alaska included. But it’s unclear what the total number of grids is in this case.
Certificates include a large colorful photo that highlights the American flag, a map of the US or a photo of a prominent spot in the country.
To apply for the Worked US Grid Square Award, and all other FT8DMC awards, you must install the UltimateAAC application on a Windows machine. That application scans your WSJT-X ADIF log file and will inform you when you’ve qualified for the award at various levels. FT8DMC issues the award in digital form only (JPG or PDF) with no printing or shipping costs. In fact, the award is completely free, like all of their other awards.