One of my first independent gear mods. I got those beads from a craft store, and the knot is just a bunch of overhand knots. ("if you can't tie a knot, tie a lot" ;) ) The original mod had only one overhand knot but the beads eventually slipped through.
I like it because it makes purging easier, but I can also feather my purge simply by slipping my fingers under the spherical bead.
