Cleaning Block Pool is a hard block specifically designed to get rid of the most stubborn dirt, lime or algae. It is the perfect tool for the most easy and effective cleaning of your bathroom and pool tiles. Its power to get rid of the most encrusted dirt is exceptional! Environmentally-friendly Great scouring power Effective Odourless Made from recycled materials Made in Spain Non-toxic Non-allergenic Does not contain chemicals How to use:Wet the cleaning stone and gently rub the surface.