Main Body Size: Hangyodor: Approx. Width 4.2 x Depth 0.5 x Height 5.8 cm. Contact Surface: Approx. Width 2.5 x Depth 1.5 x Height 2.3 cm Main materials: Acrylic, Steel The key ring cannot be used on surfaces that are curved, matte, or made of glass May not be suitable for use on materials that are difficult to adhere to, such as silicone, leather, cloth, or items with uneven surfaces Easily attachable to smartphones with adhesive stickers You can enjoy customizing it to your own preference by attaching your favorite mascots, straps, and other accessories