About this 3D model

This is a set of model atoms that can be connected together with flexible tubing to create molecular models. I've created them to assist me in my tutoring of high school students in chemistry. True, these can be bought in scientific book shops, but then they are incredibly expensive. In addition, you never get S+, O+, O-, and N+ to build ozone, sulfur oxides, nitrogen oxides and derived substances. With this set of drawings, you can print your own, you can freely extend your set if you need more, and with the added SCAD files you can even customize them.