P72 quasi-shuttle is a period 72 oscillator (a twin bee shuttle variant) with found by Jason Summers in August 2005. It consists of two B-heptominoes being hassled by two figure eights and two unices. In about 20 generations the B-heptomino is flipped into a century, which is then flipped back into a B-heptomino. Although this looks at first sight like a shuttle, it isn't really, because each side of the oscillator uses a different hassling reaction.
- 84P72.1 at Heinrich Koenig's Game of Life Object Catalogs