POLYPROPYLENE LINER DISCOUNT PACKAGE - 4 FOR $8
This polypropylene fabric is intended for adding filters for re-usable masks. It's polyspun, 2 oz per square yd as recommended. The manufacturer states: wash gently, air dry. My supplier has washed a yard 3x and it washes and dries extremely well with no visible difference to unwashed fabric except that it becomes a little softer.
I would recommend washing it separately from the mask and lay flat to dry. Since I have just received this fabric, I have to rely on the manufacturer and supplier for best care practices.
PRICE INCLUDES SHIPPING.