Red or black metal, spring action of this feeder makes it easy for you to fill, fun to watch the birds and other critters get the whole peanuts out.  The style takes the birds longer so you can see them longer. Jays, chickadees, nuthatches and titmice will love it.  Squirrels and chipmunks will have a challenge and fun to watch getting the whole peanuts out. And try they will unless you hang it from a pole with a baffle. Helps distract them from other feeders you may have.  About 13 inches in diameter.  Takes whole, in-the-shell peanuts only. Do not use salted peanuts.