A polarization cloak was a sophisticated cloaking device used by Ramurantracers to hide themselves and their ships. It used a sophisticated polarization technique that causes sensor scans to pass right through it.
Tracer ships could fire weapons through the cloak, while remaining untargetable themselves.
However, the presence of cloaked ships might be deduced through proton surges.
The personal version of a polarization cloak could be disrupted by a magneton sweep.