os smileworld - pack of 4 custom fit dental nightguard -bundle set 5 tools -retainer case -retainer seater,removal tool, brush, carry bag -used as teeth whitening tray | tmj appliance| sports guard os smileworld smileworld - premium set 4 units instant mouthguards, and tjm appliances.the bundle set include: retainer case- design with 2 air holes for ventilation , and five more essentials retainers accessories . perfect to clean the mouth guard, and bring it wherever you like. ☑️the smileworld mouthguard is softens in hot water and moldable to fit perfect for all . multi porpose- can be used as teeth whitening tray, mouthguard sport protection , and as tjm appliances for instant relief . ☑️ bpa free , made in usa with medical grade .