ABoK#2498 (The Ashley Book of Knots), the double tatted bar, is on the same page of the book as the double tatted chain I previously posted as a paracord bracelet/watchband/lanyard.
I've used it here as a paracord lanyard and added some skull beads in the loops between the alternating ring/cow hitches as they're sometimes called. I finished with a lanyard knot, the two working ends coming out the center of the knot then trimmed/melted/tucked. I used foliage green and coyote brown colors of 550 paracord and a swivel clip.
The pattern is also easily done as a paracord bracelet, with or without the skull beads.