6RB9:
reference: The pore structure of Clostridium perfringens epsilon toxin., Savva CG, Clark AR, Naylor CE, Popoff MR, Moss DS, Basak AK, Titball RW, Bokori-Brown M, Nat Commun. 2019 Jun 14;10(1):2641. doi: 10.1038/s41467-019-10645-8. PMID: 31201325

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