JoshDV, what CRASH said is correct, the psi rating has nothing to do with whether the cover will fit!
It only has to do with the air you put in
Its more to do with the shape and ci.
Is yours a normal fiber tank or a steely?
And Draxxus does make a stubby bottle but thats a 68 and not a 70 right CRASH? Cant remember.
I think the only 70 stubbies made are by Dye.
JoshDV, why dont you just post a pic of your tank and we will try to tell you if it fits.......