Thank you for viewing. This is a keychain designed by Albert Einstein, a German theoretical physicist. It can also be used as a necklace by attaching a chain. Size: 26mm Frame color: Silver Material: Stainless steel, glass ※The 500-yen coin is not included for comparison. ※Please note that we do not respond to price reduction requests or comments asking for a discount unless you are purchasing multiple items. If you wish to purchase multiple items, or if you have other photos or designs you would like, please feel free to comment. We can also create custom designs. Accessories, key rings, straps, pendants, keychains, small items, necklaces, keychain, keyring, astrophysics, space, quantum theory, Albert Einstein, general relativity, special relativity, photoelectric effect, Brownian motion, Albert Einstein, light quantum hypothesis, mass-energy equivalence, Einstein's equation, Albert Einstein, Albert Einstein, Albert Einstein, theoretical physicist, Nobel Prize in Physics