Prevent Large Birds From Feeding You choose - let all birds feed or selectively feed to smaller songbirds.
The Squirrel Buster Plus lets you decide which birds can access your feeder. Adjustable Posi-Grip Perches can be shortened or extended by rotating the perches. Shortening the perches will deter large birds like Grackles and Starlings, but smaller birds like Chickadees and Finches will still feed. Want something in-between? No problem. Just shorten the perches to a medium length, and you will still attract birds like Grosbeaks and Woodpeckers.
The squirrel-proofing mechanism can also be used to prevent large birds from accessing the seed. The weight sensitivity of the spring can easily be adjusted by turning the plastic casing around the spring. This will cause large birds to close the seed ports when landing on the feeder, preventing access to the seed. Again, you decide how much weight will close off the seed ports, so you can adjust the feeder to attract or deter different birds. With the Squirrel Buster Plus, you can selectively feed only the birds you want to see at your feeder!