Multiflex Hose has a clear FDA formula PVC with black vinyl helix. It is abrasion-resistant, flexible, and is resistant to mild chemicals and saltwater. This hose is primarily used for bilge pump discharge, potable water tank fill, and drains (sinks, shower, livewell, and scupper). Uses 147 right-hand thread cuffs. Do not attach to thru-hull fitting below the water line. Do not use ethylene glycol-based antifreeze in hose. Sierra Part #116-141-2003B.