There will be a parts order form in the box. Order the AC adapter or you will have to replace batteries quite often. Re-chargeable batteries are not recommended by the manufacturer. I also needed the larger cuff which I ordered with the form. This model has been replaced so you won't find the parts online. Use the paper form that comes with it.

This machine is professionally made by a company that specializes in DME (durable medical equipment) for professional application, which is why I bought it over the companies that market directly to lay persons interested in non prescribed home health monitoring. It works well, is simple to use, accurate, quick, and not painful or scary to use (takes the reading and releases you fast) . For the lay person it also immediately tells you the meaning of the reading, so you can help the MD track your vital signs. Highly recommended.