Tweak Hearing Replacement Tubes for Tweak Focus+T and TweakConnect Hearing Amplifiers | Dome, Small (1B) RightBrand: Tweak Color: Dome Features: SMALL TUBE SIZING: The 1B size tubes are 64 mm long and 28mm from bend to bend. Please see the sizing chart for reference VENTED DOMES: Helps reduce ambient noise and are used for those who prefer more bass sound WHEN TO REPLACE: Tubing should be replaced 2 to 3 times per year or when they become soft, discolored, kinked or damaged EASY REPLACEMENT: Easy on and off HYPOALLERGENIC MATERIALS: Made of soft,