????? Awwa C504: ?? ?? ????? ??? ??????

?? ???? ??????? Awwa C504 ?????? ?? ???? Shijiazhuang Deye Piping Industry Co., Ltd. ?? ?? ???? ?????? ?????? ?????? ?????? ?? ????????? ????????. ?? ????? ??? ?????? ??????? ????? ?????? AWWA C504? ??? ???? ????? ?????????? ???? ??????? Awwa C504 ????? ????????? ?? ??????? ?????? ??????? ???? ????? ????? ?????? ?????? ????????? ????????. ?????? ????? ???? ?????? ????? ??????? ??? ????? ??????? ????????? ???? ????? ?? ??????? ??????. ???? ?????? ??????? ??????? ????? ????? ???? ?????? ??? ????? ?? ???? ?????? ??????? ???? ???? Shijiazhuang Deye Piping Industry Co., Ltd. ???? ??????? Awwa C504 ?? ?????? ?? ??????? ????? ????? ?????? ????????? ??????? ???????? ????????. ???? ????? ???????? ????????? ????? ???????????? ??? ??? ?????? ?????? ??????? ?????? ??????? ?????? ?? ??????. ???? ??????? ???????? ??? ???? Shijiazhuang Deye Piping Industry Co., Ltd. ?????? ??? ?????? ??????? Awwa C504 ????? ?????? ???? ???? ?????????? ??????????