Astonish Power Clean toilet bowl cleaning tablets do all the hard work for you, simply unwrap the tablet and place into the toilet bowl, leave for 20 minutes for the foaming action to work deep into the U-bend to remove limescale, calcium, and rust, then brush and flush. For heavily soiled toilet bowls use 1 or 2 tablet and leave overnight. Leaving a fresh eucalyptus fragrance. Vegan Society Approved. Cruelty-Free International Certified.