Stainless Steel Utility Wire 6 ft. of .020 inch (1.83 m x 0.5 mm) mil-spec grade, stronger than brass, won't get brittle in frigid cold, multiple uses This is mil-spec grade safety lock wire (Type 302/304 MS20995 C 20) as commonly used on aircraft, spacecraft and race cars. It is stronger than brass wire, both in tensile strength and in resistance to fatigue, so it is less likely to break in use or in twisting. It is also less subject to embrittlement in very cold conditions. Being tougher, it can be more difficult to break if the survivor has no wire cutters (multi-purpose tool - Leatherman, etc.), so instructions for breaking it are included in the annotated Contents List.