The Hunter ACV is ideal to be used on sites with extreme elevation changes within a single zone. Easily adjust to the proper check height and insert this remarkable product in between the riser and sprinkler head. If you've ever used an HCV before, you know just how simple this is – it's the easiest to adjust drain check valve available and can handle elevation extremes up to 32 feet. However, what you probably don't know is that it is now constructed to schedule 80 specifications, making it more durable and long-lasting than ever.