These face masks are essentially made up of 3 layers. The middle layer is an open cel foam that is 1/4" thick. It is similar to the foam used as a filter in air conditioner units. This material is fused with a soft fleece fabric on one side which acts as a liner, which is the fabric that comes in to contact with you face. (see photo)
The third fabric on the outside is a lycra/spandex.
There is also soft 1/4" elastic used to go around the ears. ( see photo )
Please be aware that they are not as effective as the N95 version in fitering out contagions and should not be considered a replacement. However, they are likely to be more effective than just fabric.
These masks are made one size fits all but there is a top and bottom to fit face more accurately. The small seam is on the top for the nose and the longer seam is on the bottom to accommodate the chin. I've also placed the logo on the left side of all of them to help distinguish top/bottom.
The masks can be washed repeatedly by machine with warm/cold water or by hand, placed in dryer on low setting or left to air dry.