Polyurethane Metric Tubing, 6 mm OD, 4 mm ID, 20 m Length, Clear Flexible tubing for water or compressed air applications Polyurethane for resistance to chemicals, oil, weather, and abrasion Ether-based material for immunity to hydrolysis and resistance to fungus and microorganisms Compatible with one-touch, insert, self-align, and miniature fittings Operating temperature range of -4 to +140 degrees F for air or 40 to 105 degrees F for water