Measuring 5.49 x 18 x 194mm SAM50 Primed MDF windowboard is designed to provide a sleek, durable, and functional finish for your windowsills. Manufactured from high-quality MDF, the SAM50 windowboard is highly resistant to warping, swelling, and splitting, even in areas with varying moisture levels. The moisture-resistant MDF construction ensures long-lasting durability, and the smooth, factory-applied primer provides an ideal surface for a perfect paint finish.