This molecular model set is ideal for someone looking to build molecules often found in basic biology through advanced biochemistry. This product is designed for science education demonstration purposes and does contain small parts. A great kit for building various compounds and molecules such as: hydrogen oxygen nitrogen hydrogen peroxide sulphur dioxide carbon dioxide water carbonic acid sulphuric acid phosphoric acid dinitrogen tetroxide disulphur tetroxide acids alkenes aldehydes amino acids urea fatty acids and many many more. Comes with a instructions a handy tool to help remove bonds and an 11-compartment storage box for easy organization and storage of pieces. Atoms & Bonds Included: (45) Carbon Black - 4 holes (25) Carbon Black - 3 holes (10) Hydrogen White - 2 holes (110) Hydrogen White - 1 hole (14) Nitrogen Blue - 4 holes (15) Nitrogen Blue - 3 holes (12) Nitrogen Blue - 2 Holes (24) Oxygen Red - 3 holes (13) Oxygen Red - 2 holes (10) Oxygen Red - 1 hole (3) Sulphur Yellow - 2 holes (8) Phosphorus Purple - 4 holes (2) Metal Grey - 4 holes (1) Metal Grey - 6 holes (30) Medium Flexible Bonds (30) Flexible Long bonds (10) Purple Short Bonds (200) White Short Bonds