Let's start with carbon fiber unidirectional cloth. Unidirectional cloth does not mean that there is only one direction containing carbon fiber filament, and it has carbon fiber in both longitudinal and transverse directions, but one direction (usually warp) has a large amount of untwisted roving, and there is only a small amount of fine yarn in one direction, which plays a fixed role, so that the carbon fiber cloth will not spread out. The strength of the whole carbon fiber cloth is concentrated in the direction of untwisted roving, and its strength has nothing to do with its own grammage, only with carbon filament. Two-way cloth refers to the two directions of force of the cloth, and it has a large number of untwisted rovings in both longitudinal and transverse directions. Some people often buy some carbon fiber cloth online to DIY, these cloths are basically carbon fiber two-way cloth. Its commonly used specifications are 3K, 200g/㎡ thickness, here it should be noted that no matter where it is produced, the civil 3K carbon fiber cloth is only T300 level.