Yes.
But in the production kit its a Climbing Technology figure 8 (not the Petzl Pirahna in Daves picture) and its a green/black rope that is the rescue line (not the red one in dave pic). Here is a description of the function:
"After setting a climbing line and tying it off at the base of the tree you simply install 2 butterfly knots, 24" apart, above the base tie. If a rescue becomes necessary a rescuer attaches the included figure 8 descender to the lower knot and the end of the rescue line to the upper knot. After taking up the slack and locking off the figure 8, with a hand on the brake line the rescuer cuts the connecting link of the climbing line between the knots with the included hand pruners. This transfers the weight of the climber to the rescue line and allows safe fast lowering.
The kit is comprised of:
100' of Teufelberger 10mm Sirius Reep Schnur with a sewn eye
(1) Climbing Technology Rescue 8
(1) Large Weaver Throwline Bag
(2) Climbing Technology Oval Carabiner
(1) Phoenix "Red & White" Hand Pruner
(1) Weaver Pruner Holster"
I wouldnt set it up like that pre-climb though, just leave it in the bag till you need it. Having less weight on the downhill side of your rope makes things easier while you are climbing.