... The products introduction as following:1, products name:Long hinges, piano hinges, car hinges, carriage hinges, stainless steel & iron hinges. ... in the joint place where need move often, for example: piano up and down cross board hinges, long doors and accessorize box ... "nine SUNS".Specializing produced various kinds of materials row hinge, piano hinge, heavy row hinge and bolt, small hinge, AA column ...