The Window Bird Feeders by Jarkyfine are large, clear plastic seed feeders designed for hummingbirds. They are mounted on windows with strong suction cups, making them easy to install and providing a predator-proof and easy-to-clean option for bird watching. This modern-style feeder requires assembly and is suitable for attracting and observing wild birds in your yard or garden. The product may contain chemicals known to the state of California to cause cancer, birth defects, or other reproductive harm.