A decorative light string assembly comprises a string of light bulb sockets electrically interconnected by an electrical cord and terminated by at least one electrical connector. A projecting portion, which comes into contact with an end portion of the balance chamber snap ring when the balance chamber snap ring rotates independently within a ring groove about a secondary shaft, thereby restricting independent rotation of the balance chamber snap ring, is provided on a latch portion of a cover member. The bottom layers are positioned between the core layer and a bottom surface metallurgy layer and include at least one bottom conductive layer that includes a material void pattern that is based upon the top conductive layer and reduces warpage of the laminate substrate. Alternatively, the monitoring device may include a wireless communication portion, and circuitry responsive to the signal and operatively coupled to the wireless communication portion. of from 2 to less than 12 mm2s in combination with a Group IV base oil having a kinematic viscosity of at least 38, the difference in kinematic viscosity between the Group I and Group IV oils in the blend being at least 30 mm2s in combination with a detergent.