【1 1/4" Brass One-Way Check Valve】This product has an inner diameter of 1.55 inches, a length of 2.5 inches, and a weight of 381g/0.84 lbs. It is made of high-quality brass with precision casting, offering excellent corrosion resistance and high-pressure durability for long-lasting performance. The thickened valve body enhances overall strength, effectively preventing cracking and making it suitable for various water supply systems【Prevents Backflow】 This horizontal one-way check valve effectively prevents water backflow, avoiding pressure drops and contamination from impurities in the water supply system. It ensures a stable water supply and maintains water purity【Superior Sealing】Designed with a precision sealing process to ensure smooth water flow while minimizing leakage risks. The built-in high-pressure copper baffle and single-swing mechanism provide a larger flow diameter and lower resistance, ensuring smooth water discharge and stable pressure【Ensure the Arrow Direction Matches the Water Flow】The valve features a double-union design for easy installation and is suitable for horizontal installation. A clear directional arrow is marked on the valve body, which must align with the water flow direction during installation to ensure proper operation【Wide Application】This check valve is suitable for non-corrosive media, including water and oil, with a wide operating temperature range of 0℃-120℃ (32℉-248℉). It meets the needs of household water supply systems, industrial pipelines, and other applications【Product Video】Video Instructions link: https://youtu.be/FipKpBHD3tI. You can also search“15982 one way check valve 1 1 4 quarter inch npt thread copper fixturedisplays” on youtube to locate the video. You can also download video by following this link: https://www.fixturedisplays.com/video/15982.AVI