D71X means the valve type is butterfly valve, wafer connection, concentric type, rubber sealing, D371X means gear operated wafer type concentric rubber seal butterfly valve, D41X means flange type concentric rubber seal butterfly valve. D341X means gear operated flange type concentric rubber seal butterfly valve. These codes are chinese valve codes and popular to understand by us.
D71X, D371X, D41X, D341X are concentric design with rubber seal, such as EPDM or NBR seal or full lined. This products are extensively used for water supply industry etc.
Welcome to use D71X, D371X, D41X, D341X at your project and we offer 18 months quality warranty after delivery..