Inner circumference: Approximately 15cm. Slight variations may occur. * If you wish to change the size (up to 17cm free of charge), please let me know after purchase. Larimar: 7mm 64-facet cut crystal: 8mm Giant clam shell: 6mm Button-cut crystal Double-strand of Opelet rubber * The knots in the rubber are not secured with adhesive. If they come loose, gently pull them back in from the opposite side of the stone. The stones may have small scratches, inclusions, color variations, dents, and natural cracks. This is handmade by an amateur, so please refrain from purchasing if you are looking for perfection. 91