Notre Dame Fighting Irish 2015 Schedule Riddell NCAA Replica Mini Helmet. The greatest miniature sports collectible ever invented! Approximately 1/2 scale versions of collegiate helmets. ABS plastic shells with plastic facemask and authentic-looking team decals. This helmet has become a staple in the collectible market for several good reasons. It's affordable, doesn't take up too much room, and showcases an autograph like nothing else! Once you start your collection you'll be hooked!