4" x 18" 304 stainless steel flexhose. Non-magnetic 304 stainless provides long life and no rust or corrosion. 

Easier to move = less friction > less wear > longer life > less down time! 
This flex hose allows for torsional movement (twist). You can extend and contract this flex easily. This allows for porper installation at its "relaxed" length, allowing for movement in both directions or "float". This also has the finest square-cut ends in the industry and deburred (handle without getting cut).

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Note: 430 and 304 are the two most common grades of stainless steel.  Both offer a durable iron alloy that can resist rust and corrosion. Typically, grade 304 provides more corrosion resistance and thus greater longevity than grade 430.