The Chill-Its 5159 Hydration Pack Bladder Cleaning Kit is compatible with all Chill-Its Hydration Packs and Replacement Bladders (sold separately). Kit includes separate cleaning brushes for the bladder, tube and bite-valve, as well as a drying rack. Bristle Material: Nylon; Bristle Length: 3"; Brush Length: 3"; Handle Length: 12".