minus joint with double thread material:iron SGS audited More than 20 years experience in special fastener field Name: minus joint with male thread ... ; minus joint; male threaded joint Ability for the material of this kind ... 201,202,301,302,303,304,316,310,430,etc Brass C28000,C37710,C3450,C27200,etc Bronze C51900,C60600,C17200,etc ...