Pneumatic Nok Seal is a type of seal used in pneumatic cylinders to prevent air leakage between the piston and cylinder bore. It is commonly made of a high-quality rubber material such as Nitrile rubber or Polyurethane, which provides excellent sealing performance, high wear resistance, and durability. The nok seal is designed to fit tightly around the piston rod and make a seal against the cylinder bore, preventing air from escaping past the piston.