I will be getting a
Firefly Hop-up SLeeve ( Soft/MILD) http://trinityairsoft.com/p-327-hop-...-fire-fly.aspx
but it does not look like the nub comes with it. What is a good nub to match up with it. From the information I've found using google, the
Element H-Hop Up seems like a good choice but might be hard to find using the group order sources. Any other suggestions for a great nub to use with the Firefly Sleeve?

edit: Illusion said The nub IS the bucking. So I edited my post above. Although some websites call the nub and bucking different things. They should call it the rubber sleeve.