MSA 10058034 Equivalent by GASCO, 60 PPM Carbon Monoxide, 1.45% Methane, 10 PPM Nitrogen Dioxide, 15% O2, Balance Nitrogen contained in a 34 Liter Disposable Aluminum Cylinder, For Use with Any and All Gas Detectors, Cylinder Connection C-10, Calibration Certificate NIST, Made in the USA