A septic surface with 16 triple points.
See Surfaces with Triple Points by S. Endrass,
U. Persson, J. Stevens
All images are created by Oliver Labs using the software surf written by Stephan Endrass and others.
Here is the surf source code of the image above.
Oliver Labs: my homepage: OliverLabs.net, my e-mail: suse TheAtSymbol OliverLabs.net