Silver Tone Medium Pi Charm Bangle Bracelet. Silver Tone Medium Pi is approx. 0.59 x 0.47 x 0.08 (HxWxD) including loop. The irrational number Pi is a mathematical constant, the ratio of a circle's circumference to its diameter, approximately 3.14. It has been represented by the Greek letter since the mid-18th century. 1.7 mm Imitation Rhodium Plated Bangle Bracelet is approx. 2.65 x 2.5 inches (W x H). Also available as a necklace, and earrings. PLEASE NOTE: Our products are lead safe, but are not intended for children 14 years and younger.