Surgical tubing in natural and black, diameter fits blowpipes snugly and does not move. Odorless, flavorless and safe for you. The black rope measures 35″ in length and the natural rope is 56″ long. These will save you money over the small retail models available online at piping websites (at $3). You will have enough for your band or your piping career! I am leaving piping which is the only reason I am selling these, they have come in handy.