For customers who have purchased the HX-F3/hx-f5 portable open channel flowmeter, the company will upgrade the original 4 and 9 types of weirs to 10 types of weirs (triangular weirs, rectangular weirs, equal width weirs, rectangular wide top weirs, garden wide top weirs, triangular profile weirs, flat V-shaped weirs, Bachel weirs, throat free weirs, and trapezoidal thin-walled weirs) for free. These two products purchased before 2023 are four types of weirs（Triangle weir, rectangular weir, equal width weir, rectangular wide crest weir）From 2023 to July 2024, 9 types of weirs were purchasedThe event will last for 3 months, including triangular weir, rectangular weir, equal width weir, rectangular wide top weir, garden wide top weir, triangular profile weir, flat V-shaped weir, Bacher groove, and throat free groove. Due to the customer's demand for measuring weir grooves, a trapezoidal thin-walled weir was added in June to provide more convenience for everyone's measurement.