the bottom layer to provide sufficient reflection characteristics for the retention of heat 0042 fig3 illustrates in schematic form the reverse face of the product of fig1 and fig4 and illustrates the structure of the warp and weft strips 22 24 forming the scrim layer 16 for ease of reference and clarity the lace coating 20 on the other surface of the product is not shown the lace coating 20 of course would otherwise cover some of the slits 26 between the warp and weft strips 22 24 described herein in greater detail as illustrated in this enlarged figure there are provided a plurality of spaced apart weft strips 22 and warp strips 24 which are interwoven to form the scrim layer 16 the intersecting warp and weft strips 22 24 can be widely or narrowly spaced apart if desired to provide slits 26 in the scrim layer 16 the width of the slits 26 can be varied as to the degree of openness by controlling the tightness of the u201c weave u201d of the scrim layer in the particular version shown the slits 26 may constitute anywhere from 1 to 15 or so of the total surface area of that face of the scrim layer so as to permit water to penetrate the product and provide moisture to the substrate layer it will be appreciated that weft and warp strips 22 and 24 need not be spaced apart per se in order to permit water penetration this is due to the fact that such warp and weft strips even though generally retained in place by the lace coating are not otherwise secured to each other and thus even slight.