We intentionally designed our Rumble Jar filters to work with Mason jars because 1) they're the best drinking/brewing/storage vessels ever made, 2) they have a truly airtight seal that prevents oxidation from happening (oxygen is the coffee killer!), and 3) they're easy and inexpensive to replace in case you lose or break it. Affordable, convenient and high quality is a rare combo! To see more about why we built Rumble Jar the way we did, have a look at our Product Details page.