GASCO | 58-411-18SO2-5 | X06NI81CP580032 | 100 PPM CO | 25 PPM H2S | 5 PPM SULFUR DIOXIDE | 0.35 % PENTANE (25% LEL) | 18 % OXYGEN | BALANCE NITROGEN | Contained in a 58L Liter Disposable Aluminum Cylinder, For Use with Any and All Gas Detectors, Cylinder Connection C-10, Calibration Certificate NIST, Made in the USA