Product Name: Type F Flange Insulation Gasket Kit
Standard: ASME B16.5
Size: 4 Inch, DN100
Pressure: Class 150 LB, PN20
Gasket Material: Neoprene Faced Phenolic
Sleeve Material: Phenolic
Washer Material: Phenolic + ZPS
Usage: Raised Face Weld Neck Flange
Source: https://www.landeepipefitting.com/flange-insulation-gasket-kits-type-f-phenolic-4-in-cl150.html