[ShelbyCSXT]

The "fresh air" tube next to the media pickup is there to allow air to lift up media on it's way to your blasting gun. If you dont have the tube, it makes it harder for the gun to pull media through (because air isn't washing over your media and lifting it up).

All the agitator does is shakes your media off the sides of the cabinet so that it can get used. But if you have plenty of media in your cabinet, then you won't have to worry about agitating it back down.