Popular carbon fiber cylinders Inquire Buy Now Product Description carbon fiber composite cylinder tank cylinder with valve specification show as below: Type 157mm-6.8l-300bar carbon fiber cylinder Outside diameter 157mm Water capacity 6.8L Height 530mm Weight 3.9kg Working pressure 300Bar Test pressure 450Bar Application SCBA/oxygen respirator/firefighting Material aluminum Storage Gas 2.04Cum3 Production of packaging Introduction