Extremely easy to use with all seed cylinders. Once sold, you gain repeat customers. Just slide the Mr. Birds' small or large cylinders onto the sturdy steel cylinder feeder and hang. Your birds will love it, they are not limited to a few seed ports so it is common to see a dozen birds at once on this feeder. Large bottom rings allow non-clinging birds to feed with ease. No assembly is required. Nothing to screw or unscrew. Durable all-steel construction. Large! 11" tall and 9.75" wide.