When selecting a factory, prioritize those with ISO 9001 certification to ensure consistent production quality. For mechanical counters, verify the internal gear material; high-quality units use metal components or wear-resistant ABS rather than cheap recycled plastics. For digital versions, ensure the LCD display clarity and battery life (typically 1-2 years) meet your requirements. Always request a durability test report showing the device can withstand at least 100,000 clicks without jamming or resetting errors.