OSI Quad Max caulk is used in tandem with James Hardie siding products. OSI QUAD Max is designed for interior/exterior use for sealing around windows, doors and siding. It bonds to a wide variety of materials without need for a primer such as fiber cement, cedar, brick, stone, coated aluminum, steel, fiberglass, vinyl, PVC, stucco, EIFS, wood, glass, concrete, masonry, flashing tapes and Kynar coatings..