The Orbit 4 pronged tetrahedral phosphorus atom is used in many biological molecular models in sugar phosphate groups as can be seen in our dna double helix model & our glow in the dark version double helix model of dna
You can use these Genuine Cochranes of Oxford Orbit Molecular Model Parts to replace missing pieces or augment any of the Orbit Molecular Model Sets & Molecular Model Kits supplied by Indigo Instruments.