Fiberglass is a material consisting of numerous extremely fine fibers of glass. Glass fiber is formed when thin strands of silica-based or other formulation glass is extruded into many fibers with small diameters suitable for textile processing. These are useful because of their high ratio of surface area to weight. However, the increased surface area makes them much more susceptible to chemical attack. Fiberglass cloth is used as heat insulating material and an excellent substitute for asbestos cloth. It is widely applied as insulation of soft or hard tubes, heat insulation covering of heater and cooler, fire resistant shell, other insulation protecting covering and insulation of watercraft equipment because of its brilliant characteristics of high intensity, low density and good insulation.