Calibration Kit includes certified concentration gas cylinders, preset flow regulators, and tubing with connectors which mate with the analyzer and gas cylinder. The tubing assembly includes a fine flow needle valve. Instrumentation grade, certified calibration gas meets FDA standards for USP oxygen analyzers. Each cylinder provides approximately 3 months of daily calibrations. Calibration gas is shipped direct from the gas supplier. Single stage, constant flow regulators are preset for a flow of 150 ml/min and have quarter-turn on/off valves for quick control of gas flow.