A whiteout vacuum is used to hold a Transformer's extracted spark in stasis. They're used by Relinquishment Clinics, presumably to hold donors' sparks while their bodies are out on loan.

Fiction

2005 IDW continuity

On finding himself in a Relinquishment Clinic, Chromedome noted that the clinic's standard retinue of equipment included whiteout vacuums. Patternism

Millions of years later, the captured and deactivated Overlord's spark was extracted and placed in a whiteout vacuum. Interiors At least, that's the cover story that was spread around. In truth, they hadn't even been able to reach Overlord's spark.... and, according to Prowl, there is no such thing as a whiteout vacuum! Remembrance Day