MSA ALTAIR Calibration 4 Gas Cylinder 34L 10048280MSA offers a complete line of calibration gas cylinders to calibrate all instruments. The gas mixture in calibration gas cylinders is certified to be prepared gravimetrically, using NIST traceable weights. The lot number and nominal value of the gas constituents in volume, percent by mass, PPM, or volume is specified on the cylinder. Use to calibrate your ALTAIR 4X 4XR portable gas detectors Standard quad gas calibration Certified using NIST traceable