4000 PLYSEAL®-V Vinyl Reinforced Insulating Mastic Used for encapsulating and sealing sub-surface and overhead cases and auxiliary sleeves, ducts and cable ends. Excellent for sheath and conduit repairs. Impervious to ozone, fresh water, salt water and soil chemicals. Vinyl film backing provides mechanical strength and abrasion resistance. Plyseal-V is preferred for cold weather applications.