The Mack CXP613, CXU613, and GU813 2007 and newer cab skirts are made of durable stainless steel. These cab skirts are designed specifically for day cab models and come in pairs. The driver's side skirt even has a block heater cutout for added convenience. With their practical design and compatibility with most Mack CXP613, CXU613, and GU813 makes and models, these stainless steel cab skirts are a reliable and functional addition to any truck.