The Ferrari F355 Berlinetta front turn signal requires a P21W bulb size while the rear turn signal uses a 1156 bulb size. The replacement chart covers 1994 to 1996 production years with corresponding bulb size specifications.
The year-by-year compatibility chart below provides a quick reference to verify the correct bulb size for your vehicle.
The Ferrari F355 Berlinetta uses two distinct turn signal bulb standards across its front and rear positions for the 1994-1996 model years, with the front using the P21W and the rear using the 1156.
Despite carrying different designations, the P21W and 1156 share identical electrical ratings of 12V and 21W, as well as the same BA15s single-contact bayonet base construction.
The P21W designation follows the ECE (Economic Commission for Europe) regulatory standard, which is the prevailing framework for automotive lighting components in Europe and much of the wider international market.
The 1156 designation follows the ANSI (American National Standards Institute) standard, which governs automotive bulb classifications in the United States and Canada.
Both bulbs are single-filament types, a characteristic consistent with their dedicated turn signal function, which requires only one light output state rather than the dual-intensity operation found in combination stop and tail bulbs.
The BA15s base shared by both bulbs features a single contact pin offset to one side of the base, which physically distinguishes it from the dual-pin BA15d base used in two-filament applications and prevents incorrect substitution in those sockets.
Although the P21W and 1156 are electrically and mechanically similar, the Ferrari F355 Berlinetta (1994-1996) specifies the P21W exclusively for the front position and the 1156 exclusively for the rear, indicating the two are not listed as interchangeable within this application.