When sourcing extraction machinery, prioritize 304 or 316L stainless steel construction to prevent corrosion and ensure oil purity. For steam distillation units, verify the heating method (electric, gas, or external steam) and ensure the condenser efficiency is sufficient for your specific botanical raw materials. For CO2 supercritical extraction, check the pressure rating (up to 50MPa) and the precision of temperature control systems, as these directly impact the yield and chemical profile of the essential oils.