The "For Him - Lava Stone Essential Oil Diffuser Bracelet" is handmade with Black Lava Stones. 

Lava stones have recently become very popular because of their ability to diffuse essential oils. They have a porous surface, allowing essential oils to naturally diffuse from them for 2-3 days!! 

Simply add a drop of your favourite oil, rub the oil along the beads and put your bracelet on.