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The quoted warrenty is 12 months from instillation or 18 months from shippment, whichever comes first. They claim that typical life of the tube settlers is 20 plus years as long as they are not walked on or exposed to sunlight for extended periods of time while located out of water.
Environmental Impact
Materials: Polyvinyl Chloride
http://www.healthybuilding.net/pvc/Thornton_Enviro_Impacts_of_PVC.pdf
Shipping and Supply Chain
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