Liquid-Plumr Full Clog Destroyer is a powerful drain cleaner that is specially formulated to take on the toughest clogs. The thick gel holds together to cut through standing water and attack built-up hair, soap scum and gunk. It gets to work fast, eliminating stubborn blockages and leaving your drain free-flowing and clog-free. Full Clog Destroyer is safe for all septic systems and pipes, including PVC, plastic, copper and old pipes. Keep your drains clear with Liquid-Plumr. Clears stubborn fully blocked drains. Special thick gel wont dilute as it cuts through the toughest clogs. Safe for all pipes, including PVC, plastic, copper, old pipes and septic systems.