FOSTER MONOLAR II MASTIC based on chlorosulfonated polyethylene rubber (formerly known as Hypalon*) is a tough, flexible, fire-resistive, elastomeric finish for protection of thermal insulation. It is also used as a vapor retarder finish for fittings.

MONOLAR II MASTIC is produced under the classification and follow up service of Underwriter’s Laboratories, Inc.

MONOLAR II MASTIC meets NFPA 90A and 90B 25/50 requirements.