Milled Fibers are finely chopped fiberglass used for many purposes. Can be used to install Single Fin Boxes, Leash Cups, FCS X2 Plugs, and more. This product is heavier and stronger than Cabosil and Q-Cell. When mixing with resin only a tiny amount is necessary to achieve the objective of adding strength. Mix extremely well prior to adding hardener. ***Warning… if you add too much Milled Fibers the resin will become lumpy and will create air pockets around your insert(s). When adding Milled Fibers to epoxy keep in mind that thickening the epoxy will heat up the resin significantly. 2oz of Milled Fibers per bag.