Thermal blanket
From Halopedia, the Halo wiki
A thermal blanket[1] is a sheet of silver-colored, thermally reflective material that is used not only to keep people warm, but also to hide their heat signatures to avoid detection.[2][3]
A thermal blanket was used by the Spartan-III's and Kurt-051 to cover Dante-G188's body inside the Sentinel manufacturing facility on Onyx to hide him from the Sentinels of Onyx.[3] It was also used on Dr. Halsey when she arrived on Onyx,[4] and later to create a primitive Faraday cage around Halsey when she was working on her laptop, to avoid detection by the Sentinels' electromagnetic sensors.[1] Thermal blankets were also used to hide armed Lotus anti-tank mines from the Covenant.[2]
