get (something) off the shelf

To obtain something that is ready made for purchase from available stock; to get something that is not custom built or crafted. We use our own custom software, so we can offer much more precision than what you can get off the shelf. If you get a hearing aid off the shelf, it'll be less expensive, but also much less likely to help you than one prescribed by a doctor. After my grandmother inherited all that money, I doubt she ever got anything off the shelf again.