I bought the Quart size bottle used with this bait.  I hung it up outdoors by the garbage can...it's completely full in a week with what must be at least 500 - 800 dead flies.  The good news is, there's no longer flies buzzing around the doors of my house waiting to get in.  The bad news is, I have to buy enough of these packages for a weekly refresh, because the trap fills up so fast with dead flies.  So, I decided today to buy the Gallon size trap to get a longer life out of the bait.