Note that I call this model old junk just for emphasis. The are not junk. They do work. But they were made for obsolete computers that use RS-232 serial ports instead of USB. You even need a separate power cord for these old devices.
See How to choose a programming device to Program Your Hearing Aids [DIY]
In the Wired Programming Devices: section look at the current choices for cabled Hearing Aid Programming Devices and the reccommendations for those devices.
The old junk serial Hi Pros may have been a good choice in the past due to low relative cost. But you can do much better today buying a mini Pro.