The keychain is in the shape of the Greek letter lambda (λ), a symbol familiar to fans of science, technology, and science fiction. Suitable for 3D printing.A 3D model of a keyring based on the Greek symbol λ (lambda), which is used in scientific disciplines to denote wavelength, decay, and other concepts. This concise and recognizable sign has long been a part of visual culture, especially among connoisseurs of science fiction, fantasy and high-tech worlds.Dimensions: Diameter 30 mmRing hole diameter 5mm