Icc or dot designation no. 3a1800 to 3a2015,uhp ultra high purity compressed argon less than 10ppm h20,normal fill 220 cubic feet capacity,k-bottle size per mil spec. Mil-a-18455b dated 20 mar 1962. Nasa owned cylinder,size 9 in. Outside dia.,51 in. High,color coded per mil-std 101b dated 3 ded 1970,top-a-gray,band-b-white,band-c-gray,body-gray,valve data: valve no. Cga 580,as differentiated by size requirement