supply of nitrogen gas, argon gas iolar grade-i, 99.996% purity with maximum oxygen content 5 ppm & dew point of 60 degree centigrade in seller own returnable cylinders containing 8.10 cub.mtr. in each cylinder or in available size of cylinders. as per drg.no. nil alt nil [ warranty period: 30 months after the date of delivery ] , nitrogen gas to is:1747-1972 technical grade in sellers own returnable cylinders of 6-7 cub. mtr.capacity, pressure- 150 kg. / sq. cms.composition: n2=99.999% 02=ppm.drg no.alt.nil as per drg.no. nil alt nil specn: nitrogen gas to is:1747-1972 technical grade in sellers own returnable cylinders of 6-7cubic meters. the gas filled cylinders supplied shall be suitable for use with 150 kgs / sq.cms capacity regulator [ warranty period: 30 months after the date of delivery ]