Koala with Joey The nanoblock Mini-Collection Series recreates micro-sized versions of all your favourite critters, dinosaurs and musical instruments. nanoblock is the original micro-sized building block. The smallest part is a mere 4x4x5 mm! Completed nanoblock Mini-Collection models are small enough to fit in the palm of your hand. Each nanoblock set comes with spare blocks, a display baseplate and detailed step-by-step building instructions.