National Galvanized Door Rail 12 ft. by National Hardware a complete solution for creating your own barn or commercial sliding door system. Crafted from galvanized steel, this durable door rail comes in a round or box rail design and includes heavy-duty hardware for easy installation and smooth operation. Primarily designed for exterior use, it also adds a stylish industrial touch to contemporary or rustic interiors, making it a versatile choice for various applications. Model Number: