Jaguar S-Type front and rear side marker bulbs use a 12961 size across both positions. The replacement chart covers 2000 to 2008 model years with corresponding bulb specifications.
The year-by-year compatibility chart below provides a quick reference to verify the correct bulb size for your vehicle.
The Jaguar S-Type uses the 12961 bulb across all model years in the specifications, covering both front and rear side marker positions from 2000-2008.
The 12961 is a Philips part number designating a miniature wedge bulb in the T10 form factor, operating at 12 volts with a 5-watt output.
The T10 designation refers to a tubular bulb with a width of approximately 10 millimeters, a standard sizing classification used across the automotive industry.
The 12961 uses a W2.1x9.5d base, which is the wedge-type base standard for T10 bulbs. The "W" prefix in the base code indicates a wedge configuration, meaning the bulb is held in place by the socket gripping the glass envelope directly rather than by pins or a bayonet mechanism.
Because the same bulb number applies to both the front and rear side marker positions on the Jaguar S-Type, a single bulb type serves both locations across the entire model range covered in the specifications.
The W2.1x9.5d base is not universally interchangeable with other wedge base types. Wedge bases vary in width and contact spacing, so substitution with visually similar bulbs of a different base code risks improper fitment or electrical contact failure.
At 5 watts and 12 volts, the 12961 draws approximately 0.42 amperes, which is consistent with the low-current requirements typical of side marker applications.
The T10 wedge form factor is widely produced by multiple manufacturers under various part numbers, though the 12961 specifically identifies the Philips version of this bulb type.