The Kruve sifter is designed to solve a common problem: the inconsistent size of the coffee grounds you get out of a typical coffee grinder.That might not sound like a big deal but it is. Coffee grounds impart their flavor differently depending on how large they are. Small ones brew fast and can turn bitter quickly, while large grounds brew slowly and don't contribute much flavor at all unless you brew them a long time -- and by that time the small grounds have ruined the coffee with their bitter taste.So that's the problem: different sizes of coffee grounds that need different brewing times, all mixed together in the coffee you're trying to make. There's no way to choose the right brewing time.I was shocked how inconsistent my grinder is: lots of tiny bits mixed in with very large ones. And my grinder is a highly-rated burr grinder, one that you'd expect to do a good job. But it's still not good enough because my coffee had a bitter taste.The culprit was those tiny coffee grounds. Even setting the grinder to "coarse" did not make them go away.But filtering them out with the Kruve works like magic. The sifter removes the grounds that are too small, separates out the ones that are too big (so you can grind them again, a little smaller if you want), and leaves you with the ones that are sized just right. You can see the difference just looking at them.It's not a lot of extra work to sift your coffee grounds. It adds about three minutes once you get the hang of it, and the results are worth it. Now I'm drinking smooth, delicious coffee. No more bitter flavor.You do throw away the small grounds (called "fines") which seems wasteful at first but it's made up for by the fact that you can re-grind the "large" grounds to get them to be just the right size and brew more efficiently. So you lose a little on the small end but you get it back on the large end, for no net loss.I'm using the same amount of coffee beans per pot that I was before sifting, and now my coffee tastes so much better.