When sourcing stretchers, prioritize load capacity, which should ideally be at least 250kg (550 lbs) for standard models and up to 350kg for bariatric versions. Ensure the frame is constructed from high-strength aerospace aluminum alloy or stainless steel for a balance of durability and weight. For hydraulic models, verify the lifting range (typically 500mm to 900mm) and the reliability of the dual-pedal hydraulic system. Additionally, check for high-density flame-retardant mattresses with a thickness of at least 50mm to ensure patient comfort and safety.