When added to the flush tank, Elsan Rinse and Double Rinse keep the toilet fresh and remove bad odours when the toilet is flushed. They also lubricate and clean the bowl. Because Double Rinse is double concentrated, it comes in a smaller bottle so takes up less of your valuable storage space. Both Rinse and Double Rinse provide excellent value for money and are suitable for all chemical toilets and cassettes. Dosage: Add 30ml of Elsan Double Rinse to the fresh water flushing tank for every 10 Ltrs of fresh water, then add the flush water.