The thick bleach formula cuts right through standing water, clinging to your toughest clogs to blast them fast. Its pro strength formula works great to remove hair clogs, soap scum, standing water, slow drains, and pipe build ups. Just pour, wait, and flush drain. Conquer tough clogs whenever they happen. Safe on metal and plastic pipes. Contains no phosphorus. When you have a clogged sink, tub, shower, or other drain, take charge and get it flowing fast with Drano products.