Make of Stainless steel,the surfaces is electroplated,which is wear-resistance and anticorrosion,strong and Enduring. This product can be folded 90 degrees and automatically in the open position through a spring activated within the hinge. Suitable for folding leg brackets of folding bed,sofas,dining tables,platforms,tables,coffee tables and other furnitures to facilitate better placement and portability. Self-Lock folding hinges are easy to operate.You just clicking the latches and fold down for more space. Easy installation and strong carrying capacity.