a small amount of resin called a binder it provides the most economical method of obtaining a high degree of transverse or bi directional strength characteristics these mats are layered with roving and this process forms the basic composition found in most pultruded products the ratio of mat to roving determines the relationship of transverse to longitudinal strength characteristics in continuous strand roving each strand contains from 800 to 4 000 fiber filaments many strands are used in each pultrusion profile this roving provides the high longitudinal strength of the pultruded product the amount and location of these u201c rovings u201d can and does alter the performance of the product roving also provides the tensile strength needed to pull the other reinforcements through the manufacturing die since pultrusion is a low pressure process fiberglass reinforcements normally appear close to the surface of the product this can affect appearance corrosion resistance and handling of the products surface veils can be added to the laminate construction and when used displace the reinforcement from the surface of the profile thereby creating a resin rich surface the two most commonly used veils are e glass and polyester resin formulations typically consist of polyesters vinyl esters and epoxies further they can be chosen to be either fire retardant or non fire retardant polyesters and vinyl esters are the two primary resins used in the.