3HBH:
reference: The first crystal structures of a family 19 class IV chitinase: the enzyme from Norway spruce., Ubhayasekera W, Rawat R, Ho SW, Wiweger M, Von Arnold S, Chye ML, Mowbray SL, Plant Mol Biol. 2009 Jul 23. PMID: 19629717

This OCA Structure page
uses Jmol, developed by the Jmol Development Team (documentation).