Sterling Silver Double Sided Medical Caduceus Necklace Oxidized Sterling Silver Charm Charm measures approximately 20 mm x 12 mm (0.79 inch x 0.47 inch) Charm Weighs Approximately 1.0 grams (4.1 grams including 30" necklace) Thin Box Chain Thickness 0.7 Millimeters (1/32 Inch) Spring Clasp on Necklace