Batstar

Its more of an oval cylinder although the shape does taper down slightly towards the roll top when it's cinched closed. I attached my Kool Stop bead jack on the other side of the bag. I wasn’t sure what size of snap hook would fit so I just purchased a bunch of 5mm versions with the same spec of shock cord. The assembled bungees are 11" in total length.One end of the shock cord gets inserted into the bottom of the cylindrical fitting and then the cord is knotted to prevent it slipping through. Snip any excess cord from the knot and pull it down into the fitting. The hook is inserted into the top and its barbed ends clicks into place. It was just sheer coincidence that the plastic loop of the hook snaps neatly on to the frame of the rack. Here are a couple of more shots with a better view of the attached bag and bungees.