on yye shop section, i went to accessories and looked at yyf hubstack tech. there, i found a lot of selections, but what i needed is the normal hubstacks. i know they come with no bearings, that is ok for me, i already have them, but do they come with the little rubber o-ring?
What yoyo are you putting the stacks on?
888 does it matter
Yes it matters, and yes it comes with the O-Rings. Just look in the picture:
http://yoyoexpert.com/product/yoyofactory/hub-stacks/view/images/stacks-white.jpg
I would kind of look at his favorites, my guess would be an 888.