Similar to the Reebok Checklight, FITGuard's object is to stop players from causing further injury to themselves in the case of a big hit.  The mouthpiece is connected to an app, thus allowing coaches/trainers to track the level of impact of every hit in real time.  In the case of a possible head injury, FITGuard could be the difference between a player doing further damage or getting the sideline assistance they require.

[via FITGuard]