You can use these covers with any type of diaper, and they are adjustable for many different sizes. I love the cute patterns to choos from. They are definitely leak-free. Even when baby has a poop blow-out that escapes a diaper, these covers will catch it! I find them a bit expensive, but so versatile and good quality that if you are planning on using them for more than one child, they are definitely worth the investment. I am using them for a second time with baby number 2 and they still look brand-new. I do not put them in the dryer to prolong their life, but they take about 30 minutes to dry after washing, so it's not a big deal.