2 oz. Sink Fast fly-line cleaner is designed specifically for sinking lines and salt-water lines. Sink Fast is a non-toxic water based silicone product that cleans, lubricates and protects fly lines from UV damage. Unlike other cleaners, Sink Fast is not hydrophobic and will actually improve sinking-line performance. Simply spray on a clean cloth and wipe the line down. No buffing or time is required to set and the product can be used directly on the water.