2mm Italian (18K-Gold Plated) .925 Sterling Silver FLAT DOME Omega Chain Necklace Nickel Free 16in, 18in- (Gold & Silver Reversible) METAL:18k-Gold over .925 Sterling Silver FLAT DOME Omega (Gold & Silver Reversible) WIDTH: 2mm LENGTH: 16in or 18in LOCK: Lobster Claw Clasp FIT: VERY COMFORTABLE