Stained Composite MDF 3-Panel Interior Barn Door SlabCALHOME primed doors are made of high quality MDF, a composite material milled in a one piece frame to withstand changes in heat and humidity better than solid wood. Each door is carefully crafted to ensure quality over time. These doors are designed for use with traditional hinges or sliding door hardware tracks. For best results with sliding door hardware, select door at least 1 in. wider than opening. 3 recessed raised panels cut in a 1 piece frame