Invisible Hearing Sound Amplifiers for Seniors and Adults Material:Medical Resin Size:1.8*1.2cm Color : Light Red for Right Ear ,Light Blue for Left Ear Package( for one ear) 1 x Hearing Amplifier 3 x Different size closed earplugs 1 x Cleaning Tools Brush 5 x Earwax Guard 1 x Size 10 battery 1 x USER GUIDE 1 x Case Precautions Q: Why do hearing amplifiers make noise A: Hearing amplifiers will amplify all sound simultaneously, including the speech and background noise, the Noise-Cancelling microphone would help to amplify more speech signal to help you to hear more clear. Q: How to reduce feedback/whistling for this hearing amplifier A: 1. Ensure the Ear Dome fits snugly in your ear canal, make the amplifier is occlusive in the canal. 2. Choose the right size ear dome, if it is too loose, replace with a larger ear dome. 3. Turning down the volume prior to insert the amplifier into the canal. 4. Make sure the pulling line is below, and the volume button/dial is above when you wearing it, to wear the device properly. Q: : The amplifier does not work/stop working/can't be heard A:1. Change a new battery, wait for 2 minutes for full optional for a new battery. 2. Clean the sound output tube to avoid the blocked from the ear wax. 3. If you still can not hear the sound, replace the wax filter. 4. Keep the amplifier dry and clean the amplifier frequently. If you have any questions during use, please feel free to contact us, our team will provide you with professional responses within 12 hours.