Selecting carbon fibre requires matching the tensile strength and modulus to your specific application. For aerospace or high-end sporting goods, High Modulus (HM) or Ultra-High Modulus (UHM) fibres are essential for maximum stiffness. For general automotive or construction reinforcement, Standard Modulus (SM) or Intermediate Modulus (IM) fibres offer the best balance of performance and cost-efficiency. Always verify the filament count (k-rating); for example, 3K (3,000 filaments per tow) is the industry standard for a balance of aesthetics and strength, while 12K or 24K are preferred for heavy-duty structural layers to reduce labor costs.