steel cock cage inquiry

i just bought a steel chastity cage very similar to this one: … L500_SY115

I’m planning a two or three hour session and I have a question: once the device is locked on, do you prefer some slack in the scrotum after it passes through the first cock ring, or should the sac stay on the other side of that initial ring? Should the balls feel taut/tight? (Obviously not too tight; i don’t want to restrict blood flow).

Essentially, is it better for most of the ball sack to be pulled through the cock ring so they hang down? Or should only the testicles themselves go through, leaving some extra skin behind?

My session will have my hands cuffed to my torso, so i won’t be able to reach back and adjust/remove the device. I’m just asking about comfort / circulation / safety concerns.