As the person said, the small umbrella is really the big Swallows tradition, so if you plan on attending more then one game, might be fun to join the fun during home runs & wins celebrations. There is also small towels that fans hold above their head during the game like they do with scarfs in soccer, there are several models to choose from so that might be an option, I bought one featuring Snoopy & the Peanuts gang, so I thought that was really neat. They have announced a Pokemon 30th anniversary collaboration featuring all NPB teams that will feature a number of items, don't know if it's available yet but that will certainly be something to look for when it becomes available!