The Volkswagen Golf side marker requires a bulb size of 12961 for the lighting components located on the exterior of the vehicle. Data for the specific bulb requirements covers the range from 1995 to 1999.
The year-by-year compatibility chart below provides a quick reference to verify the correct bulb size for your vehicle.
The Volkswagen Golf front side marker position uses the 12961 bulb for 2015-2018 model years, with the specification noting these vehicles are equipped with halogen capsule headlamps.
The 12961 is a Philips-numbered miniature wedge bulb in the T10 form factor, fitted with a W2.1x9.5d base and rated at 12V, 5W.
The P21/5W is an ECE-standard dual-filament bulb with a BAY15d bayonet base rated at 12V with filaments at 21W and 5W respectively. Its dual-filament construction distinguishes it technically from the single-filament bulbs listed elsewhere in these specifications.
The Volkswagen Golf (1997-1998) front side marker position calls for the P21/5W, while the 1999 model year carries two separate entries: P21/5W for early production and 12961 for late production vehicles.
The 2000-2002 front side marker position returns to the 12961 bulb, the same type used in the late 1999 model year.
The 12821 rear side marker bulb shares the same T10 form factor, W2.1x9.5d base, 12V, and 5W rating as the 12961, making them technically equivalent despite carrying different Philips part numbers.
The rear side marker position transitions from the 12821 to the 5008 between the 1999 and 2000 model years, representing a change in both bulb type and base style.
The 5008 is an ANSI-standard single-filament bulb with a BA15s bayonet base rated at 12V. It is described as a lower-wattage variant of the 1156 bulb family.
The BA15s base of the 5008 and the BAY15d base of the P21/5W are both bayonet-style fittings but are not interchangeable, as the BAY15d features offset pins to accommodate its dual-filament design.
The W2.1x9.5d wedge base used by both the 12961 and 12821 is physically distinct from the BA15s and BAY15d bayonet bases, meaning wedge and bayonet bulbs serve separate socket types within these specifications.