There seems to be a minor mix-up with the product code. "REN-OS201FN" is not a finger exerciser, but rather the manufacturer part code for the Ninja Artisan Electric Outdoor Pizza Oven & Air Fryer

If you are looking for hand health tools from the wellness brand RENPHO, they make the highly-rated RENPHO Cordless Hand Massager with Heat, which uses multi-level air compression to relieve finger numbness, wrist strain, and arthritis