I did have an inaccurate spelling, the product is ProFlex and seems to be a pretty standard application for fiberglass as well as rubber. It contains a fiber fill that acts something like a thin sheeting of fiberglass if I am reading correct. You can perform patch work with this compound the same as using the fiberglass patch. What I fof esd use a caulk tape to form a gasket under the roof top fan vent put new caulk around that and then after that cures coat the surface with the Proflex to form a barrier. I will be using this ( weather permitting ) over the Thanksgiving week-end. I have already replaced and recaulked one of the 4 plumbing vents as well as the main fan vent. Next 3 more plumbing vents, 1 bathroom vent fan, 3 antennas, 1 spot light, refrigerator exhaust vent, tv antenna and so on and so on, and a partridge in a pear tree. I will be a lot more happy with new caulk and a good seal. And what better time than nice warm fall week-ends.
