It contains 408 atoms which are 11+ types of different elements(Please note that metal elements some of metal ions, such as sodium, so you can form NaCl); 530 bonds which contains different length to meet your needs and 36 Charge-Clouds. With this kit, you can build all common molecules and ions. What makes this kit unique is that it can build all the common geometries of metal complexes: octagonal, square planar, and trigonal bipyramidal and linear. Carbon, oxygen, nitrogen, , phosphorous all have 4 tetrahedral holes,which allows to build these types of molecules and ions that have more than the normal valence( having positive formal charges). Advanced Learning Science Education Kit: Atoms and bonds that are perfectly suited to being connected and disconnected easily without making your fingers hurt. We also included a link removal wrench to make the task easy. Perfect chemistry model kit for modeling simple and small to more advanced and complex chemical structures for schools, students of all ages, researchers and enthusiasts. Fun and interactive early learning molecular set for kids of all years and for use in the classroom. Size: 14.2 x 11 x 5.2inch color:Multicolor Material:Plastic+PVC Package Contents: 1 set x Chemistry Molecular Model Kit Only the above package content, other products are not included. Note: Light and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.