The unit has 10 ports with 4 I.D. openings for a deer's muzzle. Accommodates the largest whitetail. With our Patented Protein/Gravity Head you get the most moisture resistant free choice feeding system available on the market today ! The Custom Designed head features a 10 degree of angle, and a 1 overhang on the feed ports. Each feed port has a drain hole to disperse any water that enters the tip of the feed port. Our patented design features an internal cone that dispenses the feed evenly to the THREE feed ports. The adjustable inner sleeve allows the user to control the feed flow of almost all feed shapes and sizes. Push it all the way up to virtually shut off the flow, or ease it down until you get the optimal flow on your favorite type of critter food.Note: Remove protein head when not in use / empty. Residue from corn/feed causes squirrels to chew on the unit when it's empty.