Double 30s???

[GunRunner]

i actually have 5 of those manifolds, and this newer one with a pro valve. The newer manifold takes the new larger al30s, so i could swap them for 40s, but ive tried 40s on the black manifold, and they wont fit. All but 4 of the 12 30s i got with these manifolds are useable. They are fun to dive, my gf is 4'11, and she can sit down with them, and walk straight upright without a problem.