r"
^(?P<unit_type>S)(?P<unit_size>\d{1,2})(?P<mounting_type>A|P)(?P<cracking_pressure>\d{1,2})(?P<sep_1>-)(?P<unit_series>1X)(?P<sep_2>/|=)(?P<pressure_rating_max>\d{1,3}|)(?P<surface_coating>J3|J5|)(?P<orifice_position>B|)(?P<orifice_diameter>\d{1,2}|)(?P<pipe_port>/2|/12|)(?P<special_version>(.|[0-9])*)$
"
gm