General Hearing Instruments domes are an essential part of your Simplicity brand open-fit hearing aids. Replacement domes not only look and feel better but they also help your open ear hearing aids fit better. Your domes should be replaced about once every three months or as often as needed, for your hearing aid to work its best. Replacing the sound dome on your device is a quick and easy procedure to perform. Use General Hearing Instruments" tubes and domes to make a slim-tube earmold for GHI Simplicity Brand hearing aid models only. The factory original replacement domes are comfortable and non-occluding. Use the filament line of the micro polytube cleaning tool to clean any debris that may poor sound quality * Six (6) pack of large size sound domes for Simplicity brand OTE hearing devices * Fits Simplicity Smart Touch, Hi Fi 270, and Hi Fi 270 models only * Micro poly tube cleaning tool along with easy to follow instructional DVD included Included: * Six pack of large original factory replacement sound domes DOMES ONLY * A micro poly tube and earmold cleaning tool * User Instruction Manual * Quick-Start Instructional DVD Warning: General Hearing Instruments original factory replacement tubes and domes will only fit on Simplicity brand hearing aids. Do not purchase if you wear a different hearing aid.