Size: microscope charm: 2cm(0.8")*1cm(0.4") double helix charm: 2.9cm(1.1")*0.8cm(0.3") chain length: 46cm(17.7")+5cm(2") with lobster clasp. Package: The Microscope and Double Helix Necklace will arrive in a velvet bag ready for gift giving. Manufacturered by CHOORO. Gift Idea: Perfect for any lover of science/biology/chemistry - Scientist Biologist Chemist Microbiologist Lab tech Science enthusiast Science Student Microbiology Student Biology teacher Biology major Biology fieldetc. Perhaps you have a scientist in your life? Or you just like research! This microscope and double helix necklace is the perfect way to express your zest for science! Material: Stainless Steel and Alloy it is lead free and nickel free.