Is it safe to store filled 510 carts without thread covering?

[3dfx-glide]

I just got a pen and distillate carts today for the first time. I only did flower before. The pre-filled 510 CCELL came with a little soft rubber covering for the threads. Is more to protect the threads, or to also prevent oil/terp leakage from the bottom of the cart when stored outside of the pen?

Safe to store in a dark place like a drawer without it?

 

[invertedisdead]

It's to keep the cartridge sealed from oxidation from oxygen, same reason we keep flower in a jar instead of sitting on the table. Some of the carts come with a cover for the top and bottom which seals the whole thing, then that's usually stored in an air tight container as well.