[Spa]

its called the nub:P

Originally Posted by Skladfin

Be careful with the hop up rubber. There are 2 things that can happen and has happened to me:

Forced it out because it was literally stuck there so it got stretched out and now it won't fit.

Lose the Hop-up rubber and your done for unless you get a new one. It's a TEENY TINY bit of piece that practically runs your hop up, without that = no hop up.

That's about it, other than that it's not so hard.