This is one of the most absorbent pads from HYF, made with five layers of organic cotton fleece, a layer of waterproof PUL inside, and backed with a choice of fabrics: the black polyester fleece with or without waterproof PUL; or black organic cotton fleece with PUL. The black wool option has no PUL layer, but is still very absorbent. All types are machine washable up to 60'. The double poppers prevent sideways slipping, and the slim design means you don't have unnecessary bulk. A slim fitting pad that hugs the shape of your body and is suitable for your heavier flow days.