The selection of factory reject battens are sized at 25x50x1800mm, ideal for projects where cosmetic perfection is not a priority and cost-effectiveness is key. These blue roofing battens come with various defects, which may include: Blue Stain: A discoloration resulting in a bluish or greyish hue within the wood. Mold: Visible signs of mould present on the surface. Fallen/Dead Knots: Knots that have partially or completely fallen out from the wood. Splits/Cracks: Splits or cracks within the wood.