Riddell mini-helmets were a set of helmets made by Riddell, a sports souvenir company.
Although primarily focusing on sport-related helmets and equipment such as football helmets, Riddell produced some based on the Star Wars franchise. Only five were created before they were replaced with Master Replicas in 2003/2004, which included Darth Vader's helmet, which had both the mask and helmet removable, as in Return of the Jedi, Boba Fett's helmet, a Return of the Jedi–era stormtrooper helmet, Luke's X-wing helmet, and C-3PO's head. The stormtrooper helmet was the rarest, with Boba Fett being second rarest. Plans for a TIE pilot helmet were considered, although since Master Replicas took over, they couldn't get further than the prototype stages.
Each helmet also came with some blueprints that described the in-universe functions of the helmet. The blueprints for the stormtrooper helmet first mentioned the Reifflex cellular padding, according to Daniel Wallace in his tie-in blog to the release of Star Wars: Darth Vader: A 3-D Reconstruction Log.