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6" 757 Double Check Detector Assembly (OSY-LM)
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6" 757 Double Check Detector Assembly (OSY-LM)
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$5,893.15 each
Out of Stock
Out of Stock
Get it Fri, Jun 16 - Tue, Jun 27

Non-Potable Water Applications

This product does not comply with the “Safe Drinking Water Act,” which requires that products meet low-lead standards in order to be used in systems providing water for human consumption (drinking or cooking). This item is for non-potable (non-human consumption) water applications only.

Lift Gate

This product weighs 400 lbs. and may require the use of a lift gate. If you do require a lift gate at your delivery, you'll have the option to add this FREE of charge when you checkout.
Free Shipping This item ships free
Easy Returns No restocking fee for 90 days

Product Highlights

Size icon
Material icon
Stainless Steel
Max Pressure (PSI) icon
175 PSI
Max Temp (F) icon
140°F Max Temp
Min Temp (F) icon
33°F Min Temp


Note: This item does not comply with the 2014 Lead Free Act. It may not be used in potable water applications as of January 4, 2014.

Series 757, 757N Double Check Valve Assemblies are used to prevent backflow of non-health hazard pollutants that are objectionable but not toxic, from entering the potable water supply system. Series 757, 757N may be installed under continuous pressure service and may be subjected to backpressure and backsiphonage. Series 757, 757N consists of two independently operating check valves, two shutoff valves, and four test cocks.

  • Extremely compact design
  • 70% Lighter than traditional designs
  • 304 (Schedule 40) Stainless steel housing & sleeve
  • Groove fittings allow integral pipeline adjustment
  • Patented tri-link check provides lowest pressure loss
  • Unmatched ease of serviceability
  • Replaceable check disc rubber
  • Specs




    Stainless Steel

    Max Pressure (PSI):


    Max Temp (F):


    Min Temp (F):



    UL/FM outside stem and yoke resilient seated gate valves


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    Ordered the wrong product? Item damaged in transit? Our 3-step process makes returning products easy – even up to a year after purchase – with no restocking fees on returns made within 90 days.
    Return Policy