Identified faces produce pairs of identical temperature circles on the CMB sphere (Cornish-Spergel-Starkman 1998).
Simply connected: no matched circles are predicted.
Wavelengths longer than the fundamental cell cannot fit. The lowest multipoles are damped relative to flat ΛCDM.
A Mollweide projection of the sky, with a low-l field aligned along the topology axis. Schematic only.
No preferred axis: the prediction is statistically isotropic.