Butyl seal is a 40 mil double-sided reinforced aggressive black butyl rubber tape used to join panels of polyethylene and polypropylene together by overlapping the edges and applying Butyl Seal in between. It is also used to adhere to concrete walls and footings when properly prepared. Butyl Seal is non-hardening and flexible. Available in 2” x 50’ and 6" x 50' rolls. Click here for Product Data Sheet. (MINIMUM $150.00 ORDER)