When sourcing stocklots, you must verify the Grammage (GSM) to ensure it meets your specific application needs (e.g., 70-80 GSM for A4 office paper, 250+ GSM for packaging board). Additionally, check the Brightness/Whiteness levels (typically 92% to 104% for premium grades) and Moisture Content, which should ideally be between 4% and 7% to prevent curling or jamming in printing machines. For specialty stocks like C2S art paper, confirm the coating consistency and opacity to ensure high-quality double-sided printing.