Backflow cones have a hollow tunnel in the middle. Use a special backflow incense burner with these, and the smoke will pour out through the bottom and down the burner like a waterfall.Fizzy Pop incense is incredibly popular in stores! It is a sweet fizzy scent that actually smells effervescent like a soda! You won't believe it until you try it!This is a bag of 25 backflow cones made by the famous Wildberry brand.