WAC Landscape Lighting extension rods are used to extend the distance between a fixture and mounting surface (spike, surface mount canopy, etc). Casted using a special k-alloy aluminum that is engineered to withstand the most challenging environments over time. Solid brass coated in bronze (-BBR finish) may be available for enhanced protection against corrosive elements and is recommended for use in coastal or marine environments. Available in 4in, 8in, 12in, 18in and 24in sizes - extension rods are 1/2in threaded male-to-female and cannot be shortened in the field.