If you've never heard of them, then you need to investigate!  They sell a variety of scent products that are wonderful!  At Lissa's, I carry the Air Moji II as well as the car unit.  Both of them use no waters, oils, flames, or  electricity.  This means no spills!  No worries that you've left a candle burning!  And, no chemical waxy smells.  They are safe for humans (and asthmatics), dogs, cats, etc. The larger unit covers a room/classroom/office.  It comes with a USB charger -- you can charge it up, move it around -- and then recharge! The battery operates a fan which disperses the scent in the air!  The car unit has an adaptor that allows it to fit in the slots of your air conditioner.  Both use the same size pod!