Household grade CMX (copper cable) has only the grade of copper cable, without the classification of optical fiber, which is the lowest grade of UL. The flame on the household-grade cable will automatically go out after spreading for 5 meters, and there is no restriction of forced blowing, and there is no specification requirement for smoke and toxicity. Household-grade cables are generally used in individual households and should not be laid in bundles. The flame propagation mode of bundled cables is completely different from that of cables.