1. Standard: DIN, ANSI, BS, ISO,JIS 2. Material: Carbon steel ,Stainless ... and BSW5)Can be made with different tensile strength, such as Class 4.6, 4.8, 5.6, 5.8,6 ... , hot-dip 7)Can be made with different standards, such as ISO, DIN, AS/NZS, GB, ANSI, BS & special standard according to the drawing.