Simulform® Co-Liners™ provide the highest degree of Structural Enhancement available for both new construction and rehabilitation of existing structures which have been damaged, or even destroyed, by impact or stress concentraion. They are a sandwich composite approach which combines the highest fastening strength of any Structural Enhancement liner in the world, with the backup protection necessary to keep the structural enhancement liner a permanent part of the structure. Simulform® Co-Liners™ have been recognized for many years as the only way to ensure an impermeable membrane for Structural Liners. Simulform® Co-Liners™ are the ultimate Structural Enhancement due to the fact that they have the highest fastening strength of any Structural liner in the world, as well as backup protection in the event of a puncture or breach.