Polyurethane Multi-Purpose Construction Joint Sealant DESCRIPTION ITLS PU 50 is a single component polyurethane based elastomeric sealant which cures under the effect of atmospheric humidity to form a flexible and resistant joint with very good adhesion on most materials. APPLICATION ITLS PU 50 can be used for bonding and caulking different materials used in the general industry : concrete, wood, aluminium, most lacquered metals, polyester, glass, stone, etc.