You can always get a roll of butyl at Home Depot.I reused the butyl that was on the headlight. Suppose I could get some from the Dynamat I’ve got left over.
Fabral 1/4 in. x 40 ft. Butyl Rubber Sealant Tape 40BT - The Home Depot
Use butyl rubber sealant tape to protect your Fabral metal roof. The tape is installed on the overlapping roof panel edge to provide a waterproof barrier on the seam. The 40 ft. roll of sealant tape is
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