We bring the desirable properties of polyester static ropes to small-diameter pull-down cord, useful at times for greater efficiency when using single-rope-technique. While not as stiff as a proper rappelling rope would be, the essentially-static properties make difficult retrievals easier. 100% Polyester means less water absorption. Large enough that a Tibloc w/ (new) Attache carabiner will grab it. Almost strong enough to rappel on doubled (but not really).
 
Please note: a pull cord is far less useful in a rescue situation than an actual 8+ mm static rope. Carrying a pull cord is for expert canyoneers in controlled conditions.