Spiral Wound Gasket with 304 Inner Ring Material Composition: Sealing Layer: 304 stainless steel + graphite filler (alternating spiral winding) Inner Ring: 304 stainless steel (centering ring) Standards Compliance: HG/T20610 Pressure Rating: PN1.6MPA Thickness: 4.5mm (typical) Sealing Face Type: RF (raised face) Applications: Flange connections in oil, chemical, and power industries for sealing under high pressure and temperature. If you need other sizes, please contact me and we will complete soon.will complete soon.