What are examples of medical devices?

It depends. Durable medical equipment is deductible only when it is ordered by a doctor and used to alleviate or prevent physical or mental illness. Those items used for general health not related to a medical condition are not deductible as durable medical equipment. 

For example, if hearing aids, crutches, a scooter, special shoes, or a blood pressure device is ordered by a doctor and treats a condition, it could be deductible. If you have a blood pressure device and a weight scale to monitor general health, they would not be deductible.

For more information, please see this IRS publication IRS medical and dental expenses