The k-carafe refillable filter allow you to use your own coffee in k-cup brewers that support the k-carafe option. Since no OEM product exists, the aftermarket variations are the only solution at this time. This filter uses a ‘flip-open’ top that does not lock, meaning it does not seal that well or stay closed all the time. Regardless, it works pretty good, the machine holds it closed for the most part, and since k-carafe pods are not currently offered in nearly the variety as k-cup pods, and cannot generally be purchased locally, this product certainly fills a void.
Conclusion: Works, but could be improved.