No, they come in 12ga only. Good excuse to buy a "real" shotgun for around the house. The shorter range also helps in semi-built-up areas.
The company found that different brands of pump shotguns worked better or worse with these rounds, which are really about half the length of a standard shell. They claim the Winchester 1300 works perfectly with them, while a Mossberg 500 or Remington 870 may occasionally misfeed. They have descriptions of simple modifications to the shell carries of both guns that will allow them to handle the stubby shells properly, while still working with the standard ones.
I was able to rack a mix of standard and stubby shells through my Stevens 510 military riot gun without trouble. Of course, that was a vey limited test.
Go out and buy that Winchester 1300 for ecurbh. You can even get it in stainless/nickel finish for marine use.
All I know is, I can go shoot up a couple boxes of shells on clay pigeons, and still move my arm afterwards! :~D My 12-guage-friends want to go have a beer and rest after one box. And my 20 is such a lovely gun.