There are two types of Tear-Aid: Type A and Type B.
Tear-Aid Type B is to be applied to Vinyl and Vinyl coated surfaces only. If the top layer of the product you are adhering the patch to is vinyl or vinyl coated you will use Type B.
Tear-Aid Type A is applied to Canvas, Rubber, Neoprene, Nylon, Most Fabrics, Plastics, Sunbrella, Gortex, Polyethylene, Polypropylene, Polyurethane, Non-oiled Leather, Acrylics, Fiberglass, Aluminum, Polyester, Hypalon, Dacron… (Do not apply Type A to vinyl). If the top layer of the product you are repairing is any of the listed materials you will use Type A.