The Behind-the-Ear (BTE) device consists of an instrument that rests behind the ear attached to a custom-made ear mould. This style may be used for all types and degrees of hearing loss. These devices can be packaged in a mini case depending on the type and level of hearing loss. A BTE device may be required where extra power is needed or where medical conditions such as humidity of the external ear canal prohibit the use of other devices. BTEs are available in several colours for hair and skin tone matching.