Fits Weber 32/36 DGV, DGAV, DGEV carburetors. The emulsioning tubes affect the relationship between the main jets and the air jets, and the RPM range where the air jets take over from the main jets. Most Ford 1600 and 2.0L applications (FF1600, FF2000, S2000, and Cortina) use F50 in the primary and F6 in the secondary. Sold individually.
Also fits Weber ADFA, DARA, DCN, DCOF, DFAV, DFD, DFI, DFM, DGAS, DHSA, DIC, DICA, DIR, DLED, DMSA, ICA, ICF, ICH, ICT, and IDA (3-barrel) carburetors.