when i first purchased this reusable k-cup filter, amazon.ca coupled it with the basic keurig model (KUB30) for single servings. not knowingly, i purchased this bundle to find out that this reusable filter is NOT COMPATIBLE with the basic model. it only works on the higher end models like KUB40, KUB60 etc... so i had to return the both of them back to amazon. BEWARE before purchasing.
upon purchasing a better and higher end machine, this reusable filter works fantastically. it is very simple in terms of operation, you open the main body to remove the metal/reusable filter inside, and fill this filter up with ur brew, seal it shut and put it in the machine.
i could not give this product 100% because it is actually sometimes quite cumbersome to refill and reuse especially if you are a big coffee drinker who wants more than 10-12oz at a time. i suggest you buy 2 or three of these to not get annoyed for that matter. atleast this way, you can fill the grind all at the same time without having to rinse and refill each time.
one last thing that contributed to a non 100% score is, the filter is quite expensive, 3 of these equates to $45CDN + taxes. but it works well and it is built solidly, and it is an investment if you intend to use your own brew of tea or coffee.
in general, keurig products are fantastic and very convenient to have. just make sure not to purchase this if you intend to use it on the most basic machine (KUB30) because it will not work.