** Shares of Reliance Worldwide Corp RWC.AX fell as much as 10.1% to A$3.46, hitting their lowest level since November 1, 2023

** Stock set for weakest trading session since late August 2023

** Water flow control solution provider posts 34.9% drop in HY NPAT to $43.7 million, impacted by U.S. tariffs and weak demand in U.S. and U.K.

** However, co announced buyback of $15.3 mln

** While softness in U.S. market and tariff uncertainty were largely known, new pockets of softness in Australia and EMEA were also a negative surprise - Citi

** Citi says new tariff costs for FY27 will likely add to challenges

** Stock down 8.3% YTD, including the day's moves

(Reporting by Shivangi Lahiri in Bengaluru)

((shivangi.lahiri@thomsonreuters.com))