The Stretchy bracelet inner length is 6.7 inches and it is elastic.Fits Most of the Size. 8mm Stone:Made of natural lava rock stones and red howlite The Black one is also Essential Oil Diffuser Bracelet,Drop the essential oil on the volcanic stone beads and the scent can remain for a long time. Good Gifts for your Dad,Mom,Girlfriend,Boyfriend,Best Friend, Son, Daughter, Roommate or Classmate. Any question or problem, please contact us. We will make sure reply you in within 24 hours, and give you the solutions as well.