The Volkswagen Golf brake light utilizes 7440 and P21W bulb sizes for the specific lighting components located at the rear of the vehicle. Data for the specified lighting components covers the period from 1993 through 2018 for the various production versions.
The year-by-year compatibility chart below provides a quick reference to verify the correct bulb size for your vehicle.
The Volkswagen Golf uses two distinct brake bulb types across its model years: the 7440 and the P21W. Both operate at 12V and 21W, making them electrically equivalent, though they are physically incompatible due to different base designs.
The 7440 is an ANSI-standard single-filament wedge bulb in the T20 form factor, specified for the 2015-2018 Golf brake lights. Its wedge base is a push-in design common in North American vehicle applications.
The P21W follows the ECE standard used in European and worldwide markets. It uses a BA15s bayonet base, a single-contact fitting that twists and locks into the socket, and is specified for the 1993-2002 Golf brake lights.
Despite sharing identical voltage and wattage ratings, the 7440 and P21W are not interchangeable. The wedge base of the 7440 and the BA15s bayonet base of the P21W are physically incompatible socket types.
The Center High Mount Stop Light on the 1995-1999 Golf uses the size 70 bulb, a miniature T5 wedge type rated at 12V and 1.4W. This is substantially lower in wattage than the main brake bulbs, reflecting its role as a supplemental high-mount signal rather than a primary brake light.
The 1993-1994 Golf Center High Mount Stop Light uses the 12961, a Philips part number designating a T10 miniature wedge bulb with a W2.1x9.5d base, rated at 12V and 5W. This differs from the size 70 used in subsequent years in both form factor and wattage.
The size 70 and the 12961 are not interchangeable. The T5 form factor of the size 70 and the T10 form factor of the 12961 involve different physical sizes and base types, making socket compatibility a relevant fitment consideration.
The shift from the 12961 to the size 70 in the Center High Mount Stop Light between the 1994 and 1995 Golf represents a change in both bulb wattage and base specification within the same sub-part position.