I love my duck. If you look at the instructions there is a way to use it as a locking pulley. I have been playing around with using it like that for SRT instead of the grigri. Then when I get to hunting height, it becomes my tether. In order for it top work like that though I run the rope back up to my hand ascender and through a small carabiner then down. When I stand up I pull on the tail, and the hand ascender and the duck automatically advances.
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