"Russian" GOST Type 7 RTJ Groove Blind
Flanges to GOST dimensional specification 12815-80 for Oval profile Ring Type
Blind Flange NPS 150 x 6.3 & 10 pressure class / RTJ D diameter205mm - Material ASTM A105N NACE MR0175
Blind Flange NPS 150 x 16.0 pressure class / RTJ D diameter205mm - Material ASTM A105N NACE MR0175
Blind Flange NPS 250 x 16.0 pressure class / RTJ D diameter 330mm - Material ASTM A105N NACE MR0175
etc.
More details,please be free to contact with me and I will offer help as much as we can.