When sourcing aluminum panels, the alloy grade is paramount; 3003-H14 is standard for strength and corrosion resistance, while 5005 series is preferred for high-end anodized finishes. The panel thickness typically ranges from 2.0mm to 4.0mm for exterior cladding to ensure structural rigidity against wind loads. Additionally, verify the coating type, prioritizing PVDF (Polyvinylidene Fluoride) with at least 70% Kynar 500 resin for projects requiring a 20-year color warranty against UV degradation and pollution.