Apiezon L grease can also be used to protect electrical contacts. The grease itself is of course an insulator, however, the grease film on a contact is so thin at the actual point of contact that it just does not interfere with the passage of electrical current except for the smallest of voltages.
To further clarify this point, Apiezon L has an electrical strength of 720 volts per mil (0.001"/25 µm). In a metal to metal contact the film of grease would be only of the order of 0.00001"/0.25 µm) or less, giving an electrical strength of only 7 volts. For contacts operating at high temperatures, use Apiezon T.
