Double HH Quality Products: Hook Up with the Best 3-point linkage parts, custom machined equipment, Double HH original hitchpins, Double HH quality products, Double HH hitchpins, Double HH linkage parts, hitchpin manufacturer, red plastisol coated hitchpins, precision machined equipment Don’t compromise, demand Double HH Quality Products! Wide range of stock and custom-machined agricultural and industrial equipment – including the original hitchpin with the red plastisol coated head and handle. Made with pride in Rock Valley, Iowa.