This kit can build both an alpha and and a beta sheet. It can also, of course build pi-helices and 3_10 helices, for those students who know about them! You will be getting the alpha helix kit, but it has precisely the same pieces as the beta sheet kit, also shown in the product images. This kit has been very useful for me to really understand protein folding. It comes with purple bonds to symbolize the hydrogen bonds, and lock-and-key planar carbons and nitrogens, which model the planarity and resonance of the peptide bond. It also comes with pink “R groups” to model the side chains of the amino acids. This kit is the easiest and quickest way to accurately visualize protein structure!