A completely-in-the-canal (CIC) hearing aid is a small, custom-made device that fits inside the ear canal and is designed to improve hearing: 

• Appearance: CIC hearing aids are almost invisible, unless someone looks directly into your ear. 
• Comfort: CIC hearing aids are custom-fit to your ear canal, so they are comfortable and won't move around. 
• Sound: CIC hearing aids are placed further down the ear canal, so they produce a more natural sound. They also reduce wind noise because the outer ear acts as a shield. 
• Controls: CIC hearing aids usually don't have physical controls, but you can control them with a smartphone app or remote. 
• Battery: CIC hearing aids typically use a size 10 battery, which lasts about 2–3 days. 
• Limitations: CIC hearing aids may need to be reshelled over time, and they can be damaged by wax in the microphone port. They may also be more prone to feedback and echoing