Fully assembled with ready to bolt on convenience. This entire intake assembly includes everything you need to replace or upgrade you carburetor to the latest design from SU (Skinners Union) This is a single HIF 44 (44mm = 1 3/4") includes air filter, alloy intake manifold, manifold gasket, manifold vacuum port plug, studs, nuts and washers, abutment bracket, mounting gaskets, phenolic spacer, red Dashpot spring, BFM needle, choke cable clip, special tuning throttle cable, white throttle cable clip, vacuum advance pipe. This is as easy as it gets for bolt on convenience.