Aluminum compression connectors are manufactured from high conductivity, high purity wrought aluminum. They are designed with sufficient mass and are electro-tin-plated to minimize corrosion due to galvanic action between dissimilar metals. The connector barrels are pre-filled with Penetrox™, Burndy oxide inhibiting compound. Barrel is designed with an internal chamfer at the wire entry to ensure smooth insertion of the wire Connectors are clearly marked with wire size, die index, color code and crimp locations bands Color coded end caps are factory inserted in the barrels to match the die color code, prevent foreign materials from entering the barrel Aluminum oxidation is not easily detected but causes resistance in a connection Aluminum terminals are dual-rated to accommodate both copper and aluminum wire and are indicated with Al-Cu on the connector