The hearing aids are designed to fit either ear, but the ear tube and earplug must be correctly positioned. To switch the Medescan hearing aid from the left ear to the right ear, please follow these steps: Hold the bottom and top (where the tube is connected) of the hearing aid. Begin turning the hearing aid device anti-clockwise while keeping the top still (where the tube is connected). Keep turning until you see the top of the tube begin to unscrew and come off, then screw in the left/right tube going clockwise.