This is a high-class combination necklace made of titanium and K18 (18-karat gold). It is lightweight, rust-resistant, and gentle on those with metal allergies. The plate has the engraving "TITAN K18 002 THz," and it is a model that has been treated with terahertz (THz) processing. What is THz (Terahertz)? Terahertz refers to "waves that vibrate 1 trillion times per second (terahertz waves)." Terahertz ore and terahertz-processed materials that emit these waves have recently been used in jewelry and health accessories. Terahertz waves are said to have effects such as: ・Promoting blood circulation ・Relaxation ・Balance adjustment Many people feel these effects, and it is gaining popularity as a "beauty and health item to wear." ※K18 parts are placed in three locations, and the design is simple yet elegant. 【Product Details】 ・Material: Titanium / K18 (with engraving) ・Length: Approximately 47cm (including fittings) ・Engraving: TITAN K18 002 THz ・Condition: No noticeable scratches or stains (please check the images) ・Fit: Fits around the neck (feels like about 45cm in actual use) Instant purchase OK Feel free to comment if you have any questions. ※There are no accessories such as a dedicated case, and only the main body is for sale. ※There may be slight errors due to manual measurement. ※Please purchase only if you understand that this is a used item.