rento Set of 4, New rento Sauna Fragrance Birch 400ml Sauna-specific aroma oil This is rento's sauna fragrance, Birch. You can mix multiple scents to enjoy an original fragrance. *Because of the risk of ignition, sauna scents must be diluted with water before use. Store away from fire and direct sunlight, in a well-ventilated place. *Enjoy the loyly by mixing 2-4 capfuls with water as desired.