One empty glass bottle for diffusing your favorite aromas practically anywhere. Just twist to open wooden cap and mini funnel (one included) to transfer your fragrance or essential oils. Tighten cap and hold with fingers as pictured and flip upside down. Within a minute or 2 you will see the wood change color to activate aroma. Hang your diffuser in the car, offices, closets, lockers, fans, and more! One random color design per order. To add a Fragrance Oil please select a fragrance oil.