I have a 40cc Echo blower engine that has 3 rings.......
imagine 3 Bowman rings.....

you really only need one and may be much better than 3 but i really hate to get into all that again. i dont care how many rings you got. more rings dont garuntee a good seal. you could have 4 rings with a worse seal than a single ring with a great seal. condition of the parts is everything and the only way to know how good a seal you have is with a leakdown testor. man i really hate to go into that again.