Completely-in-the-Canal (CIC)
+ For mild to moderately - severe hearing loss
+ Very small one - piece hearing aid
+ All components contained in a custom - fit, hard - molded plastic shell
+ Fits inside the ear canal
+ Barely visible or not visible at all in the ear canal
Mini-Canal (MC)
+ For mild to moderately - severe hearing loss
+ Small one - piece hearing aid
+ All components contained in a custom - fit, hard - molded plastic shell
+ Fits mostly in the ear canal and extends slightly outside of the ear canal
+ Barely visible in the ear
In-the-Canal (ITC)
In-the-Canal-Power (ITC-P)
+ For mild to moderately - severe hearing loss
+ Small one - piece hearing aid
+ All components contained in a custom - fit, hard - molded plastic shell
+ Fits outside the ear canal
+ Slightly visible in the ear
Half Shell (HS)
+ For mild to severe hearing loss
+ Larger one - piece hearing aid
+ All components contained in a custom - fit, hard - molded plastic shell
+ Fills a portion of the bowl of the ear
+ Visible in the ear
In-the-Ear (ITE)
+ For mild to severe hearing loss
+ Larger one - piece hearing aid
+ All components contained in a custom - fit, hard - molded plastic shell
+ Fills the entire bowl of the ear
+ Visible in the ear
Behind-the-Ear (BTE)
+ For mild to profound hearing loss
+ Larger two - piece hearing aid
+ Contained in a case that is worn behind the ear
+ A molded plastic case behind the ear, and a earmold extends into the ear
+ May be barely visible depending on case color and earmold color

Open-Ear (OE)
+ For mild to moderately-severe hearing loss
+ All components contained in a case that is worn behind the ear
+ A molded plastic case behind the ear, and a clear, tube extends into ear canal
+ Barely or not at all visible
TYPES OF HEARING AID TECHNOLOGY
There is no single hearing instrument that is suitable for all types of hearing loss. The type you need depends on your individual hearing loss and the nature of that loss.