When sourcing pencil sharpener moulds, the most critical factor is the mould steel grade. For high-volume production, you should prioritize H13 or S136 stainless steel to ensure corrosion resistance and a long mould life (typically 500,000 to 1,000,000 shots). Additionally, verify the cavity number (e.g., 16, 24, or 32 cavities) to ensure it aligns with your injection molding machine's capacity and your required production cycle time, which should ideally be between 15 to 25 seconds for maximum efficiency.