Seals are the key components of hydraulic cylinders, hydraulic components, rotating shafts and related mating parts. The quality of seals is related to the normal operation and service life of the whole set of equipment. Therefore, how to correctly understand and select seals is crucial for users. Therefore, we have made this set of seals manual based on years of experience in sealing applications. The manual for cylinder seals of oil cylinders mainly introduces dust-proof ring series products, piston seal series products, piston rod seal series products, pneumatic seal products, guide rings and guide belts and other series products.