It's a tough high-density polyethylene that comes in two wall thicknesses. Use Regular to line metal tubes or nest inside larger tubes (for making small heads, or adding cones).
Our Thick-Wall Micro tubing (requires .031" Dia pin) is tough enough to tie small patterns directly on the tubing - for example, small streamers or big nymphs. Most off-the-shelf cones and beads fit Micro Tubing.
package is 1 36" length of micro tubing.