By the 13-oz can or by the case (12 – 13-oz cans), TC-11 Aerosol is the most convenient application system for small corrosion prevention projects. Best for everyday use. TC-11 is a penetrating corrosion inhibitor. TC-11 is a unique product because it is the only product on the market that penetrates into interstitial spaces and leaves a film that prevents corrosion and functions as a lubricant. Interstitial spaces are the gaps between the two pieces of metal that are bolted together. They range from 20 millionths of an inch upward, depending upon the smoothness of the metals.