Behind the ear hearing aids have a main shell section, an earmold and a connecting tube. The main shell houses all of the electronics and the battery. The BTE hearing aid hooks over the top of your ear and rests behind the ear. Traditionally a plastic tube connects the hearing aid to a custom earpiece called an earmold that fits in your ear. More recently many of the hearing aid brands have introduced thin tubing, (thin plastic tubing) which connects BTEs to the ear. Thin tubing can be used with a generic dome or a custom tip. Thin tubing is very discreet but it is not suitable for all hearing losses.