The Big Bale Buddy is a bag style feeder made out of heavy duty, open weave, UV treated polypropylene. The Small fits a round bale up to 4 feet 4 inches in diameter. (measure across the flat end of the bale).The Big Bale Buddy covers the bottom and sides of the bale so that the animals must pull the hay from the top of the bale (flat end). A strong elastic holds the feeder up and they are unable to get at the sides of the bale to unravel it. As the hay gets eaten the feeder collapses down with the bale, keeping the hay in side. It is excellent for keeping your hay clean and contained in muddy and windy conditions, and can be turned on its side in rainy weather to help keep the hay dryer. The Big Bale Buddy has a 100% safety record and will pay for itself in saved hay many times over during its years of use. Shakes clean and folds up into a tidy bundle when not in use.