After using the electric wax warmers these diffuser seem old fashion. But before the electric warmers we use to use these diffusers all of the time. They are great to use for Aromatherapy. You place a tiny bit of your favorite essential oil in the top section, light the tea light candle and as the candle warms the oil, you will be surrounded by the beautiful scent you choose. Lavender, jasmine, lemon balm and passionflower are four fantastic scents to use for relaxing! These little diffusers are approximately 3 3/4 inches x 3 inches. All of the diffusers I have in stock are different but the same size. Each diffuser comes with a small vial of scented oil (not from my stock but from the company I purchased them from) and a tea light candle.