When sourcing a beer can filler, prioritize the filling technology (e.g., isobaric/counter-pressure for carbonated beverages vs. gravity for still liquids). Key specs include Dissolved Oxygen (DO) pickup levels, which should ideally be below 30-50 ppb to ensure shelf stability. Additionally, verify the filling accuracy (typically ±1-2ml) and the seaming quality, as a precise double seam is critical to prevent leaks and CO2 loss. Ensure the machine supports CIP (Clean-In-Place) systems for high hygiene standards.