38x19mm Treated Graded Roofing Laths. 38x19mm section. Nominal 1½x¾". Commonly known as slate laths. Pressure treated, graded roofing battens. Always put glass onto timber laths, equally spaced for the piece of glass, so the weight is evenly distributed.Never put the glass down directly onto concrete, or other hard flooring, as this will break the glass.
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