blind flange class 150/600/900 1.Size:4'' * 150lbs 2.Material: A105 3.Standard: ... .5 4.Qualification;API,ISO,CE blind flange class 150/600/900size 1/2" to 24" ASME B16.5 24"to ... ,F316,F316L,F321,F347,F310F44F51,A276 S31803, A182, F43,Etc)Alloy steel(ASTM A694 F42,F46,F52,F56,F60,F65,F70 ...