Product Description: We recommend that one essential oil for one time to avoid flavor smell mixing. Material: rosewood/black walnut volcanic stone Size: 35mm in diameter X 15mm in height (without clip height) Function: Used to diffuse fragrance in the car can absorb essential oil and diffuse slowly The amount of essential oil dropping into the aromatherapy wood is up to you and the style of your essential oil usually 3-5 drops is enough. It need drop slowly until essential oils absorbed by the diffuser otherwise the essential oil will leak from the bottom. A special gift ideas with good design and purpose for aromatherapy fans and anyone who loves essential oil. It is a ideal gift for family and friends. A perfect gift for birthday/Father s Day/Mother s Day/Valentine s Day. Natural tool for relieve tension and stress in daily busy work driving sleeping long-distance travel business trips. The effect of the diffuser may not be obvious at the initial stage of use. The diffuser needs to be raised for some time. As time goes by it s function will gradually increase. The aroma will also last longer and longer!!