This coming Saturday in Chase Field, the Arizona Diamondbacks will have a ceremony to retire No. 51 in honor of the franchise's first Hall of Famer (that is, the first player wearing the D-Backs hat on his plaque), Randy Johnson.

To coincide with the event, the Snakes are going to wear hats with a Big Unit patch on the side. It's pretty awesome. Here's a look, courtesy of New Era.

That is sweet. Those hats are now available for purchase and that's a must-have for any D-Backs fan.

Johnson's No. 51 will be the second number retired by the Diamondbacks, after Luis Gonzalez's No. 20. And, of course, every team has Jackie Robinson's 42 retired.

Johnson won four consecutive Cy Youngs, three ERA titles and led the league in strikeouts five times with Arizona. He also played an integral role in the franchise's 2001 World Series championship, sharing MVP honors with fellow starter Curt Schilling. He was elected into the Hall of Fame this past winter with 97.3 percent of the vote.