Product Name: Ring Type Joint Gasket
Type: Ring Type Joint (RTJ) Gasket
Shape: Octagonal
RTJ Type: R Type
Standard: ASME B16.20
Material: Soft Iron
Size: 4 Inch, R37
Pressure Class: Class 900 LB
Surface Coating: Electroplated Zinc Coated
Source: https://www.landee.cn/soft-iron-rtj-gasket-r-type-asme-b16-20-4-in-r37-cl900.html