My jet pack weighs a little too much, but I haven't weighed it. I believe the more accurate way to do it is like the diagram below. However, I had originally done it this way for my stormtrooper, back when I wore the voice amp behind the chest piece - hooked and velcroed to the two velcro pieces on the sternum strap (not elastic, but probably a better idea). I may, one day try to replicate the setup in this diagram. I recently got an old scuba buckle and would like it to all go together correctly - might even be more comfortable. If your jet pack is at all heavier, add some good padding to the shoulder straps on the harness.
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