SpectraCool with Advanced Corrosion Protection Air Conditioners deliver the same reliable enclosure cooling solutions as the SpectraCool Indoor/Outdoor Air Conditioners with advanced corrosion protection. Two levels of corrosion protecton include: Level 1 - protective coatings on all exposed copper tubing and solder joints, condenser coil and thermostat. Level 2 - all protective coatings in Level 1 plus a coated evaporator coil. Foam wrap added over protective coatings on thermostat.