Rena Medical/Lab Grade Silicone Airline tubing is prized for its flexibility and ozone resistance. Silicone tubing remains soft and pliable even when subjected to ozone and the 1/8" inner diameter will fit standard airline tubing adapters in addition to larger 1/4" fittings. 8ft roll. Very flexible but with a slightly thicker wall. New formulation is also chemical resistant if using for liquids.