This filter and handle came with my K575, makes better tasting coffee than the Keurig it replaces. I don’t even know that one’s number, bought about 8 years ago, still operating. But lacks these newer features, and the carafe capability. 

The K575 is a wonderful machine in its own right. The filter makes it better. Often I use city tap water. The only thing I’d ask is to design the filter to also reduce lime, if that’s possible.