Citronella Essential oil are very safe and effective to repel mosquitoes and keeping them away on your households. It is made from pure oil of citronella grass. Thus, it is organic, biodegradable, non toxic, no deet and of course 0 chemical. It comes with 30ml pure citronella e.o And 2 assorted colorful fumeballs. How to use: In your fumeballs, you'll only need to put 2-3 drops of citronella e.o then hang it anywhere you want on any part of the house..esp places where mosquitoes are always hiding and/or grouping. Don't worry of its scent because even though mosquitoes hates it, it has a calming and a relaxing effect on human and even safe for babies 6 months and beyond. *just don't put it directly on your skin. And of course, keep away from reach of children.