GASCO 602 Calibration Gas Mix, 1% Carbon Monoxide, 1% Carbon Dioxide, 1% Methane, 1% Ethane, 1% Ethylene, 1% Acetylene, Balance Nitrogen contained in a 600 Liter Disposable Aluminum Cylinder, For Use with Any and All Gas Detectors, Cylinder Connection: TBD Gas Specific, Calibration Certificate NIST, Made in the USA