Wing inserts have two layers of flannel with one layer of hemp fleece in the core. They can be used on their own in a Ric Rac base pad, combined with another wing insert or used on top of a trifold. These are great if you tend to spill over on the wings of your pad, as it gives added wing absorbency. If you tend to bleed off the pad a little higher up, you can simply position the insert to have the wings where you need them.