Test gas in reusable cylinder "Ecomini" with 100 ppm hydrogen (H2) in synthetic air. 0.85 litre cylinder size at 70 bar Volume: approx. 60 litres Please return the empty cylinders to Esders GmbH after use. We will refill them. As a thank you for your contribution to environmental protection, you will receive a free pack of 100 Esders Connect measurements.