When selecting a factory, you must prioritize material quality and thermal management. For lamp holders (sockets), ensure they are made of heat-resistant PBT plastic, ceramic, or high-grade brass to prevent melting or electrical fires. For integrated LED fittings, verify the Luminous Efficacy (lm/W) and the Color Rendering Index (CRI >80). Additionally, check the Ingress Protection (IP) rating—IP20 is standard for indoor use, while IP65 or higher is mandatory for outdoor or industrial fittings to ensure dust and water resistance.