Thermal blanket

A Thermal Blanket is a human device used not only to keep people warm, but also to hide their heat signatures to avoid detection.

History
One was used by the Spartan-III's and Kurt to cover Dante's body inside the Sentinel Manufacturing Facility on Onyx to hide him from the sentinels of Onyx. It was also used on Dr. Halsey when she arrived on Onyx. Thermal blankets were also used to hide armed Lotus Anti-Tank Mines from the Covenant.