Screw on the power ring

Turns out you could screw in a little cat-tail style throw lever, but that's not really a good idea. It won't un-nitrogen-purge your scope, but its the screw that connects the outer power zoom ring that you touch with your hands to the inner power zoom ring that's part of the inner tube. If you unscrew that, you can misalign them and have the potential of losing it, tho I'd imagine it prolly wouldn't damage anything fiddling around trying to find it. Also, not a good idea to have a big probe sticking out the side of you scope that goes all the way through to the surface of the inner tube.

Source: Various images of scopes "cut away" showing how the internals work n' whatnot. Found these particular images that show a screw going in through the hump on the zoom ring to the zoom ring on the inner tube. I couldn't find any actual written-word sources, so you're going to have to trust your eyes. (Also, given this can change from scope to scope, brand to brand, depending on just how they're built, or if there even is one at all, so milage may vary on that bit about it being a blind hole that won't void your nitrogen, but it'd be pretty stupid and fragile to build it that way I'd imagine, if you've got a good scope.)

And for those of you with bad eyes

Hope that helps!

Thank you