Instant Power Heavy Duty Drain Opener will clear blocked sinks and drains and will even dissolve hair and grease clogs. Safe for PVC piping and septic tanks when used as directed. Warning: Poison - harmful or fatal if swallowed. Corrosive - drain chemicals can cause severe burns and blindness. Always wear protective safety goggles and long rubber gloves when using and working on clogged drain pipes containing drain chemicals. Keep locked up and out of reach of children. Do not use in the presence of children or pets. Always read the label thoroughly before use.