The Nike Force Mouthguard features a boil and bite fitting system to provide a custom fit. Extended O-Flow breathing channels help maximize oxygen intake and bite pads offer a cushioned feel for consistent comfort. Quick release strap included. Extended O-Flow breathing channels help maximize oxygen intake even when you bite down Moldable, boil-and-bite design for a personalized fit Bite pads offer a cushioned feel for consistent comfort Quick release strap included One size fits most