The present invention provides a mat having at least one primary area and at least one secondary area and adapted to reinforce a polymeric matrix material, the mat comprising (a) a first layer comprising a plurality of generally parallel, essentially continuous glass fiber strands oriented generally parallel to a longitudinal axis of the mat, at least a portion of outer surfaces of the first layer glass fiber strands having applied thereon at least a partial layer comprising at least a partially dried residue of first coating composition which is compatible with a polymeric matrix material, wherein at least a first portion of the first layer glass fiber strands are positioned within the at least one primary area at a primary strand density and at least a second portion of the first layer glass fiber strands are positioned within the at least one secondary area at a secondary strand density which is different from the primary strand density; and (b) a second layer comprising a plurality of randomly oriented glass fiber strands positioned within the at least one primary area and the at least one secondary area and adjacent to a surface of the first layer, at least a portion of outer surfaces of the second layer glass fiber strands having applied thereon at least a partial layer comprising at least a partially dried residue of a second coating composition which is compatible with the polymeric matrix material, wherein the first and second layers are joined to hold the mat together.