supply of shield gas-mixture consisting of 95-99%shield gas-mixture consisting of 95-99%,shield gas-mixture consisting of 95-99% argon gas to specification is:5760- 1998 or latest gr ade 3 & 1-5% oxygen gas to specification is:309-2005 or latest, filled in cylinders with capacity of 7 cum an d maximum working pressure of 150 bar with purity certificate for mig welding purpose.note: (1) the supply shall be made in requisite quantity in a phased manner as per delivery schedule issued by railways 2) batc h wise test certificate of gas shall be provided along with every supply make: praxair/inox/mspl/sg/kig/so l or equivalent [ warranty period: 30 months after the date of delivery ] ]