Profile: Crain Mfg., Inc. specializes in manufacturing a variety of custom metal products and accessories. Our product line includes trailer jacks, trailer couplers, refuse containers, storm shelters and custom fabrication products. Our brand includes Stallion™. We offer a full line of trailer jacks for the stock, horse and equipment trailer industry. We provide a complete line of couplers for gooseneck and bumper-pull trailers.