China Hexagon Head Plug: ASTM A182 F51 Hexagon Head Plugs, MNPT Ends, ASTM A182 GR F51 (UNS S31803) Material, Class Rating 6000#, 3/4 Inch (DN20). 

Type: Hex Head Plug, Hexagon Head Plug. 
Material: ASTM A182 GR F51 (UNS S31803). 
Class Rating: 6000#. 
Size: 3/4 Inch (DN20). 
Ends: MNPT.