The biOrb Water Level Guide & Feed Hole Plug. Used to help create a seal over the feeding hole to provent water deposits. It also comes with a feeding spoon to use while feeding your fish.
 Part # 46032
 
Plugs feeding hole at top of aquarium
Small spoon aids in scooping food from food container 
Prevent and slows evaporation and water deposits from forming around feeding hole.
Provides a visual water line level for the Classic Life Series Tanks