Hummer's Galore, Hummingbird Feeder Cleaner Flexible cleaning brushes for feeders with a 1" or more bottle opening. Also great to clean feeder bases. 5" Red bristles, curved at bottom to reach down in bottles and bases. Works well with 8 to 32 oz bottles that have an opening of at least 1". Total size of brush is 16.5" and cleans feeders and bases. See other Hummers Galore products for designer feeders, nectar, ant moats, and replaceable bases. Fill feeder with mild detergent and shake vigorously. Scrub bottle interior and base with brush and rinse thoroughly to protect your hummers.