The More Birds Hummingbird Feeder Cleaning Kit is perfect for cleaning small feeder crevices and nectar feeder bottles with small and large openings. The brush's handle is made from metal, while the foam sponge is made from nylon. A portal brush is also included for thoroughly cleaning narrow nectar ports. The sponge brush is designed for use with glass and plastic nectar bottles. Keep hummingbirds healthy and clean your nectar feeders today!