Only the tiny removal handle of the hearing aid shows outside of the ear canal.
Until recently the CIC instruments were accepted as the smallest on the market. They are still incredibly discrete and available at most technology levels. As component size has reduced, manufacturers have been able to fit more circuitry inside their CIC systems to the extent that most offer these aids with a wireless option. This means they can be used with a streaming device or a remote control which will give access to programme and volume adjustments. The CIC use a size 10 battery, which should give 4-5 days battery life if not using wireless functions.