Major Safety has been in the business of providing quality gas detection and safety equipment for over 30 years. We are committed to providing you with knowledgeable sales and service of quality equipment ranging from reflective vests and earplugs to engineered fall protection systems and various carbon monoxide calibration gas. Carbon monoxide calibration gas is available in quantities from 17-103 liters, depending upon which carbon monoxide calibration gas you order. We understand the importance of properly calibrated monitoring systems, so when you talk to us you can be assured that we never consider it a bother to meet your needs, so feel free to contact us TOLL FREE at 800-446-8274 or email sales@majorsafety.com to discuss the exact carbon monoxide calibration gas you require!