Possible Clues:

• Clog-busting product
• Product that works, and is stored, under the sink
• Product with a Clog Talk webpage
• "Unstoppable" cleaner
• Cleaning product that anagrams to 33-Down
• Clog-removing brand
• Offerer of clog-busting tips
• It might work on a block
• Brand of clog remover
• Pipe-clearing product