A2 stainless steel A2 grade steels are the most widely used stainless steels. They are used for kitchen equipment, chemical industry appliances, fasteners and much more. Also known as 304 grade stainless steel, A2 stainless steel contains around 18% chromium and 8% nickel, giving it high corrosion resistance and good heat resistance. Knuckle Hinge A Roller Node Hinge is fitted to the outside of the door and frame. It consists of two parts, each with a rolling knot that inserts into the other part, creating the pivot axis for the door. When the door is closed, the rolling knot is completely inserted into the other part of the hinge, making it more discreet and less likely to be caught or damaged. Below is the table of technical dimensions: A x B c d à˜ of screw à˜ of countersink 90 x 50 4,5 1,5 4 6 Difference between Rolled Node and Protruding Node Hinges Protruding Knuckle Hinges are often considered more aesthetically pleasing than Roller Knuckle Hinges, as they are virtually invisible once the door is closed. However, Roller Node Hinges can be stronger and more durable than Protruding Node Hinges due to their more robust construction. The choice between these two types of Hinge will therefore depend on the specific needs of each project.