Carb, After-market, replacement for your stock carb. This is a nice copy of the Honda carb that will be more suited for the budget minded buyer. Nice quality build, good casting and needs no jetting. We tested this unit and found it to run very nice with no tuning needed. WE HAVE NOW ADDED ITEM 166 FOR FREE , With the addition of this cap now, this item is plug and play exactly as purchased for bolt on carburetors. No other supplier offers this carb with this option at this price. On the Early models You will need to remove your intake manifold studs. Also your stock air filter assy will not clamp around the outside of this carb unit. We do sell an adapter(Z22D) that will allow you to slip your air filter assy inside of this rubber boot. If you desire a clamp on filter, you will need to purchase an after-market air filter assy #P53-28. If you need a new throttle cable the #Z148 is the gray version, the #Z8 is the black version.