Features: Designed for balancing chemical equations, advanced science learning. Nice for organic structures, cyclic compounds, and biology models. Improve hands on ability and exercise children to develop g ood creativity. Made of superb p lastic material, it is easy to install and long-lasting. Comes with 4 diffferent optional molecular model kit for your diverse choice: for your different needed. 1 122PCS Molecular Model Kit Set((59 Atoms Model+62 L ink Keys+ 1 T ool) 2 179PCS Molecular Model Kit Set(76 Atoms Model+102 L ink Keys+ 1 T ool) 3 240PCS Molecular Model Kit Set(86 Atoms Model+153 L ink Keys+ 1 T ool) 4 444PCS Molecular Model Kit Set(196 Atoms & 234 L inks & 3 Orbitals & 1 Short l ink remover tool) Specifications: Material: Platsic Types: 4(Optional) 1 122PCS Molecular Model Kit Set((59 Atoms Model+62 L ink Keys+ 1 T ool) 2 179PCS Molecular Model Kit Set(76 Atoms Model+102 L ink Keys+ 1 T ool) 3 240PCS Molecular Model Kit Set(86 Atoms Model+153 L ink Keys+ 1 T ool) 4 444PCS Molecular Model Kit Set(196 Atoms & 244 L inks & 3 Orbitals & 1 Short l ink remover tool) Item color: Multicolor Package size: 1 2 3 : 235 * 170 * 35mm 4 230 * 170 * 70mm Package weight: 1 : 450g 2 : 560g 3 : 650g 4 :850g Paking list: Types: 4(Optional) 1 122PCS Molecular Model Kit Set((59 Atoms Model+62 L ink Keys+ 1 T ool) 2 179PCS Molecular Model Kit Set(76 Atoms Model+102 L ink Keys+ 1 T ool) 3 240PCS Molecular Model Kit Set(86 Atoms Model+153 L ink Keys+ 1 T ool) 4 444PCS Molecular Model Kit Set(196 Atoms & 234 L inks & 3 Orbitals & 1 Short l ink remover tool)