Turns out that four of these were actually commissioned/used by the Colorado Rockies for Opening Day in the year 2000. They were made by the Boulder Blimp company and have extremely durable construction with 2.3 Amp Blower Fans, with velcro across the top so they can be "filled" with Helium Balloons and then "ripped" open to release 'em. Now I just gotta figure out what to do with 'em!
Just after buying these, the Colorado Rockies starting winning games like you wouldn't believe - 14 of the last 15 games of the season. They then beat San Diego in a one-game playoff for the wild-card spot, and went to the playoffs. So I started putting the monster baseballs on the front yard on game days for good luck. The Rockies then went all the way to the World Series ... but unfortunately, got swept by the Boston Red Sox in 4 games. But it was one heck of a good run!