When evaluating cotton ball thread, buyers must focus on Material Composition and Thread Count. Ensure the product is 100% Combed Cotton for superior softness and strength. For decorative or craft use, verify the Ply (e.g., 3-ply or 4-ply) to ensure it meets the required thickness. Additionally, check for Colorfastness (Grade 4 or higher) to prevent bleeding during washing or exposure to light, and confirm the Tensile Strength to ensure it can withstand high-speed machine processing without snapping.