3M Primer 94 Ampules can be used to promote adhesion of 3M tapes and other adhesives to surfaces such as polyethylene, polypropylene, ABS, PET/PBT blends, concrete, wood, glass, metal, and painted metal surfaces. Using the primer sticks is highly recommended to treat vehicles and boards to promote the strongest possible bond between Stompgrip and the surfaces where grip is being applied, especially along the edges. This is especially important when applying grip to challenging surfaces like plastic side panels, frame rails or areas that see heavy abuse from riding boots or braces. Sold as a kit (two sticks).