When sourcing OGM (Oval Gear Meter) flow meters, you must prioritize measurement accuracy, typically requiring a margin of error within ±0.5%. Ensure the body material is compatible with the fluid; aluminum alloy is standard for petroleum products, while stainless steel is mandatory for corrosive chemicals or food-grade liquids. Additionally, verify the flow range (L/min) to ensure it matches your pump's output, and check that the maximum operating pressure meets your system requirements to prevent housing rupture.