This tech tip docks a haul bag using a Petzl Pro Traxion hauling device. First, haul the bag up to your body level leaving about 4 to 6 inches of space between the ‘protrax’ and the water bottle that is protecting your knot. Do not jam the bottle up against the device or you will not be able to release the system.
Next, take the extra lower out line that is attached to the haul bag and make a Munter hitch and connect it to a locking carabiner. Then make a Mule hitch, take a bite and then make a loop that pulls through it that you then tie into an overhand knot. Back it up with a carabiner through that loop.Now your bag is secure via the lower out line. But you need to release the haul line so the bag’s weight is completely on the lower out line. Using the jumar still attached to the haul line, pull down enough to release the cam lock on the protrax device and unlock it so as to release the weight of the bag and take the protrax out of the system.
Now you can prepare the protrax device for the next lead pitch. Once the next leader is ready to haul you can easily release the overhand knot and use the Munter hitch to slowly let out the line as your partner starts to pull up the haul bag. This allows you to use the lower out line to keep the bag from swinging. The line will easily release itself from the locking carabiner when you run out of line.