The unit has 5" 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 4" 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 t..