Unisex SMALL/MEDIUM (7") Diffuser Bracelet, handcrafted from solid black, 8mm Natural Lava Bead. These beads hold the oils' scent and therapeutic aroma exceptionally well! All materials have been tested to withstand application of essential oils. Apply 1-2 drops of your favorite Essential Oil to the porous stone of the bracelet. The scent and aromatherapy benefits will last anywhere from 12-48 hours! Happy Diffusing!