Don't waste your money
I don't understand all the good reviews.  Description on Amazon says crush the tablet and sprinkle on carpet before vacuuming.  The tablet has a bit of moisture in it, so doesn't crumble.  It turns into a gummy mess. I then opened another and put in the vacuum canister.  Hardly smell any freshener when I vacuumed. Maybe if you stick your nose really close to the vacuum, you can get a very faint smell.  Definitely not worth the price. RETURNING.
Rating: 1 stars