Molecular surface representation of two antibodies interacting with the same antigen. PDB entries 1fdl  and  1yqv  were matched on the Y chain and then antibody structures from PDB entries 1igt  and  1igy  were matched with the Fab fragments from PDB entries 1fdl  and  1yqv. Immunoglobulins heavy chains were printed in red and green, while light chains are in yellow. The antigen (Hen Egg White Lysozyme from  1fdl ) was printed in white. Each component is provided as a separate stl file. A .py session file usable in Chimera is also provided to help the assembly. The model was created to help to teach Biochemistry and Molecular Biology at the undergrad level. Great for teaching structural biology and for visualizing molecular movement.  Details on the structure and implications are available on PDB101: https://pdb101.rcsb.org/motm/21.