Orca Composites Breather was developed to replace fiberglass and Osenberg cloth as a breather and bleeder. Orca Composites Breather is a unique, high melt point, polyester that is easy to cut and slit to narrow widths. This unique, high melt point, polyester that is easy to cut and slit to narrow widths. 4 oz x 60" W x 100 yards.