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.Dragon's Blood, an ancient fragrance made from a reddish plant resin, is said to have cleansing, protective and healing properties. It is a resinous, heady and slightly sweet fragrance that is popular for use in ritual and magic.This is a bag of 25 backflow cones made by the famous Wildberry brand.