supply of calibration gas mixture (with gas concentration and quantity.calibration gas mixture (with gas concentration and quantity.,calibration gas mixture (with gas concentration and quantity certificate) in 0.5 litre w/c alum inum canister filling pressure : 20 kglcm2, with septum arrangement to withdraw sample along with fine co ntrol needle valve and pressure gauge : std gas methane - 1000 ppm, ethane - 1000 ppm, ethylene - 1000 ppm, acetylene - 1000 ppm, hydrogen - 1000 ppm, carbon dioxide - 5000 ppm, carbon monoxide - 5000 pp m and nitrogen balance. make : spantech uk, chemtron mumbai or equivalent. [ warranty period: 30 mo nths after the date of delivery ] ]