Safety is paramount in railway components. Buyers should request Non-Destructive Testing (NDT) reports, specifically Magnetic Particle Inspection (MPI) and Ultrasonic Testing (UT), to check for internal casting defects. Key performance benchmarks include the buffing and drafting capacity (the ability to withstand compression and tension), fatigue life cycles (minimum 500,000 cycles), and impact toughness at low temperatures (e.g., -40°C for cold-climate operations). Always verify the interoperability of the coupler with existing rolling stock to prevent decoupling incidents.