We can supply 10,000 28L type 1 (steel) CNG cylinder per month. Our cylinders have been in Iranian market for over 4 years with great customer satisfaction. Specifications: Volumn: 28L. Standard: ISO 11439-2000. OD:232mm. Length:860mm. Weight: 35kg. Material: 34CrMo4. Process: Tube forming. We also supply 57L, 62L, 65L, 75L, 82L, 101L, 113L type 1 cylinders as well as type 2 (fiber wrapped) cylinders.