Spec 44 cable has a dual wall construction that combines the characteristics of radiation cross-linked polyalkene and polyvinylidene fluoride (PVF2) to provide an insulation system that offers a temperature rating of -65ºC to +150ºC in a small, light weight, soldering iron resistant cable that is also impervious to most solvent, fuels and lubricants. Spec 44 wire and cable is highly flame retarded, non-melting, mechanically very tough and is easy to handle and install using conventional tools. Radiation cross-linking prevents cold flow of the insulation, a recognised problem of some uncross-linked materials.
Spec 55 cable is insulated with modified radiation cross-linked ETFE polymer and its small size considerably reduces the size and weight of electrical harnesses. It has a temperature rating of -65ºC to +200ºC and combines the easy handling of a flexible wire with excellent scrape, abrasion and cut-through characteristics.
Both are supplied with tin-coated and silver-coated copper and silver-coated, high-strength copper alloy conductors while the Spec 55 can also be made with nickel-coated copper conductors. Both cables demonstrate a total resistance to electrical arc tracking under wet and dry conditions at aircraft system voltages and are not susceptible to UV or moisture degradation.
The cables conform to MIL-W-22759/32-35 and /41 to /46 and NEMA-WC-27500 (Cables) Defense Standard 61-12 Part 33.