Made of indium, this foil is more thermally conductive than thermal interface materials (TIMs) made of plastic. By efficiently pulling heat away from components that produce heat, such as CPUs, this foil lets you use smaller forced cooling systems to extend battery life. It’s also softer and more ductile than paste and putty, covering surfaces better to minimize airflow gaps and increase heat flow. Unlike paste and grease, this foil won’t leach out from between surfaces over time, nor will it dry out and lose effectiveness. It’s clean, easy to install and reposition, and requires no surface preparation. Foil is corrosion resistant and doesn’t need special storage.

Foil with 48% tin has greater tensile and shear strength than foil without tin, but is less thermally conductive.

A safe alternative to mercury in thermometers and thermostats, gallium transfers heat and electricity without toxic vapor that can be inhaled. Also known as Galinstan. Its low melting point means it's liquid at room temperature. When used next to parts that generate concentrated heat, it dissipates the heat quickly, making it good thermal interface material. It also allows electricity to pass throughout it, so it's often used in switches and electronics that must bend and flex.

Gallium clings to both metallic and nonmetallic surfaces such as glass and quartz. However, it eats away at most metal when used at high temperatures and dissolves aluminum even at ambient temperatures.

When choosing gallium, keep in mind its composition. The higher the gallium and indium content, the better it is at transferring heat. Gallium with tin reduces the melting point, but also decreases how well it transfers heat.