The in-the-canal hearing aid has patient selected physical components and patient selected electronic components. The construction of the hearing aid and the method of providing a hearing aid for a particular patient's hearing impairment are such that a patient may personally select the best suited hearing aid during the testing process and walk away with the hearing aid he or she has personally selected. This is accomplished by allowing the patient to select a form fitting shell with a malleable covering having a hook and twist which precisely conforms to the patient's own ear. The patient then listens to sounds with or without background noise and from various directions using electronic components which conform to the specifications of the hearing aid and personally chooses those electronics which best aid or assist the patient's hearing loss. These electronics are then quickly inserted into the same shell that the patient has chosen for testing purposes and the patient may leave with the hearing aid that he or she has personally selected during the testing process. Repair or replacement is as easily accomplished by replacing the personalized shell if physical discomfort occurs or by replacing the electronics if a sound environment exists which was not anticipated during testing. The result is a truly personalized and personally chosen prothesis which is capable of on the spot delivery.