CLENID Granule Sink Drain Opener 140 g can be easily used in sanitary and drainage pipes made of plastic, PVC or any other material. Method of use: prepare 2 liters of boiling water, carefully pour the granules into the tube. Carefully pour boiling water down the drain. After waiting for about 1-2 minutes, open the faucet and run cold water. If the blockage is not sufficiently opened, repeat the procedure.