The "All-In-One" is almost every type of head gear all in one bridle.
All of the components are removable and interchangeable, allowing you to customize the bridle to fit your needs. 
 
When all of the pieces are on it, it functions like a Game Changer or Crossway.
 
You can take the noseband off to have a headstall with a built-in bonnet (which is much less bulky than a traditional bonnet tie down).
You can take the bonnet strap off and leave the tie down on to have a rope poll bridle with a built-in tie down.
You can take the bonnet strap and tie down off to just have a rope poll bridle.
Or you can take the whole rope poll off and swap it for a leather crown and leave the tie down on to have a bridle with a built-in tie down.