Sold out on manufacturer’s website. Please note that the bag of clear connectors has a small tear in it, allowing a few of those pieces to leak into the box, but this set has not been used. Description from website: Our Tangle Protein Building Set is considered one of the most accurate protein building sets for students and bio-chemistry enthusiasts to learn about the world's bio-molecular structure. Our kit is robust and most suitable for training purposes as well as theoretical explorations due to the kinesthetic learning possible when working with a Tangle. Not complicated by excessive amino group functions the Tangle Protein Set is ideal for all ages to learn the basics of protein structures. Tangle Protein Set comes with instructions for making Streptococcal, Ubiquitin, ῳ-Conotoxin and you can always visit the Protein Data Bank for more inspiration http://www.rcsb.org/pdb. Tangle Proteins allow you to build different proteins using various shapes of plastic pieces which represent the different amino acids. You are given simple instruction for how to create the different proteins and also explanations as to the functions they play in the body so you can learn while you build. . . you learn a lot about how proteins really work – you can hold, inspect and manipulate them, which you cannot do with a computer model." New to Poshmark and want $10 off? Sign up using referral code BLACKSMOKETABBY and get $10 off your first purchase!