When sourcing 1.5mm aluminum sheets, you must first identify the Alloy Grade (e.g., 1xxx for general use, 3xxx for corrosion resistance, or 5xxx/6xxx for structural strength). Ensure the Thickness Tolerance adheres to international standards like ASTM B209 or EN 485, typically requiring a precision within ±0.02mm to ±0.05mm. Additionally, verify the Surface Finish (Mill Finish, Anodized, or Brushed) and Temper Designation (such as H14 or H24), as these directly impact the material's formability and hardness.