General Hearing Instruments tubes and domes are an essential part of your Simplicity brand open-fit hearing aids. Pair of Medium (Men) Simplicity Hearing Aid Poly Tubes not only look and feel better but they also help your open ear hearing aids fit better. Your Micro Hearing Aid Poly Tubes and domes should be replaced about once every three months, for your hearing aid to work its best. Replacing the micro poly-tube onOpen-Fit Hearing Aids 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. Pair of Medium (Men) Simplicity Replacement Micro Hearing Aid Poly Tubes: * One pair of mens size (medium length tubes) replacement micro poly tubes 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: * One pair of mens size (medium length) original factory replacement micro poly tubes PAIR ONLY * One pair of both Medium and Large domes * A micro poly tube and earmold cleaning tool * User Instruction Manual for the Open-Fit Hearing Aids * 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.