The Hunter HCV Check Valve HC-75F-75M is a top-adjustable anti-drain valve designed for 3/4" irrigation connections. It installs between the riser and sprinkler head to prevent low-head drainage, reduce puddling, and conserve water on sites with elevation changes. Adjustable retention height compensates for elevation changes up to 11 m (approx. 32 ft). Top-access adjustment — set or fine-tune without removing the valve from the riser. 3/4" female inlet x 3/4" male outlet for direct fit to standard sprinkler risers. Constructed to Schedule 80 specifications for enhanced durability and pressure resistance. Simple, compact design minimizes the need for extra fittings and simplifies installation. Includes an installation and adjustment guide for quick setup. Ideal for residential and commercial irrigation systems where reliable anti-drain performance and durability are required.