[pct-l] cuben

[Dan Ransom]

i believe cuben is fabric made from laminated woven spectra thread.
it was originally used for sails on boats, and has been adapted for
lightweight backpacking gear.  it is stronger than silnylon, by
weight, in tension, but obviously can puncture easily.

it's expensive because it is so niche, and because spectra itself is
very expensive.  pretty sure there is only one manufacturer for cuben,
hence why it stays so expensive.