Professional long-lasting grade drain line made of high-quality PE material with inner black liner, highly flexible, anti-corrosion, durable for indoor and outdoor use Interior grooves are smoothed with a black liner that offers protection from the sun's harmful rays and reduces drain friction which can lead to a build-up of sludge, scum and other accumulations resulting in drain blockage. 26 ft. long triple fitting 5/8 in. ID tubing with 16 mm or 18 mm connections, fits securely onto standard 5/8 in. male drain adapters Cut for precise installation and maximum use - the line finished is 26 ft. length with fittings on each end and cut marks every 19.68 in