This is a morphine molecule necklace. Morphine is an alkaloid obtained from opium poppies, a component of opium, and a source of heroin. It is named Morphine after Morpheus, the dream god of Greek mythology, because it "removes pain like a dream." It is still prescribed as an important analgesic/sedative drug under strict regulations in each country. If you are a geek or a science student, why don't you try wearing it to show your sense of science? It is also recommended as a small gift for science people! Also, it is perfect for those who are not interested in science but are looking for unique accessories. The chain length is 45 cm, which is easy for both men and women to use, and it can be adjusted to about +4 cm with an adjuster. The size of the structural formula part is about 3.5 cm x 3.5 cm. Available in gold, silver and black colors. The material of the structural formula part is made of rust-resistant and wear-resistant anodized aluminum, but please avoid to expose it to sweat or water for a long time, or to rub it on a hard object. Also, please note that unevenness may occur on the surface during aluminum oxidation. Since anodized aluminum is a soft material, it may bend when force is applied. If it is deformed, gently bend it in the opposite direction to return it to the original shape, but be careful not to bend or return it too many times and it may break.