18K GOLD PLATED: All gold-plated JPL jewelry is plated with 18K gold. 18K gold contains 75% pure gold and 25% other metals, thus making it a higher quality of gold compared to 14K (which contains only 58% pure gold). SIZE AND ADJUSTABLE CHAIN: The chain measures 17.7 inches (45 cm). Adjustable with two additional hooks, the chain can be shortened by .78 inch or 1.5 inches. A lobster clasp allows for easy closing. SKIN-FRIENDLY JEWELRY: Appropriate for sensitive skin. The high-quality materials and craftsmanship of the pieces mean they will not corrode or irritate the skin, ensuring they can be worn on a day-to-day basis without issues. AVAILABLE IN THREE METAL HUES: Available in .925 Sterling Silver Plated Rhodium, in 18K Rose Gold Plated and in 18K Gold Plated.