one uses Trapezoid threads (hard to crossthread) between the BOV and hose nuts, so it will NOT thread into the Inspiration hose nut. You have to unclamp the hose and clamp it on our nut. Used with KISS, Prism, Optima, Ouroboros and many other CCRs and SCRs
the other comes with the Inspiration thread that will screw directly on the Inspiration hose nuts.