1.sofa hinges,used on sofa,bed and chairs. 2. 180 degree, 3 to 5 positions 3. the cheapest sofa hinges of this kind the sofa hinge is mostly used on sofa and bed, and it can also used on some chairs, folding furnitures.1. product name: sofa hinge, furniture joint, sofa connection parts, chair adjustor.2. material: steel3. size: there are usually two kind of size, the small one is 152mm like C47, ...