Thank you for viewing! This is a keychain featuring the design of Volvox, a type of green algae. It uses phosphorescent material, so it glows in the dark when illuminated by lighting or a UV light. It can also be used as a necklace by attaching a chain. Size: 26mm Frame Color: Silver Materials: Stainless steel, glass ※The 500-yen coin is not included for sale and is for comparison purposes only. ※Please note that we do not respond to price reduction requests or comments asking for a discount, except for bulk purchases. If you would like to purchase multiple items or have a design you would like us to create, please feel free to contact us in the comments. Accessories, key rings, charms, straps, pendants, keychains, small items, necklaces, keychain, keyring, glow-in-the-dark accessories, phosphorescent, Archaeplastida, biology, Chlamydomonas, gonidia, Green algae, Tetrabaena, Gonium, Eudorina, flagella, Chlamydomonadales