Check Wire Markings: Legitimate products should clearly display specifications, voltage ratings (e.g., 450/750V), certification marks, and other relevant information. Random inspections conducted by a quality control agency revealed that 38% of unmarked wires suffered from insufficient cross-sectional area.
Test Flexibility: A compliant flexible wire should not exhibit cracking in its insulation layer after being folded in half five times; furthermore, the number of broken copper strands should not exceed 5% of the total strand count.
Verify Flame Retardancy: Apply a lighter flame to the wire's outer sheath; once removed from the flame source, the material should self-extinguish within 30 seconds. Fire safety experiments have demonstrated that flame-retardant-grade wires can extend evacuation time by 2 to 3 minutes.