6X8N:
reference: A defined structural unit enables de novo design of small-molecule-binding proteins., Polizzi NF, DeGrado WF, Science. 2020 Sep 4;369(6508):1227-1233. doi: 10.1126/science.abb8330. PMID: 32883865

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