A 5,000,000:1 scale model of a DNA double helix to stop your cuff falling open. This looks great in steel or semi-precious metal. Alternatively, if you want a bright and cheerful cufflink as a talking point I also offer this model in colourful plastic. Each cufflink is around 3.5 cm x 1cm, but the actual size of the DNA is 7.5 nanometers long and 2 nanometers across - that's 0.000000002 meters and about 50,000x thinner than one of your hairs!
Please also check out my Small DNA Cufflinks: http://shpws.me/Qhj0