Product Name: Insulation Gasket Kits
Gasket Type: Type F
Pressure Rating: Class 900 LB, PN150
Thickness: 6 mm
Gasket Material: PTFE Reinforced with Stainless Steel SS 316 Core
Sleeves: Mylar
Washers (Double): G10, Carbon Steel, Zinc Plated, Hardened Steel, Teflon Coated
Seal: Spring Energized Teflon Seal
Source: https://www.landeepipefitting.com/class-900-lb-insulation-gasket-kit-ptfe-gasket-g10-washers.html