Collection: T10 Bulbs

T10 and W5W: Two Designations, One Bulb

The designation T10 comes from the American nomenclature and is widely used in English-language catalogs, Japanese catalogs, and many specialized French websites. It describes the physical format of the bulb: T for Tubular (cylindrical glass shape), 10 for the diameter in mm.

The designation W5W is the European CEE standard that describes the same bulb electrically: Wedge, 5W, tungsten. The two designations are strictly equivalent — you can buy either one interchangeably.

Uses of the T10 Bulb

• Parking lights (front position lights) — the most visible use
• Rear license plate light — must be white
• Interior dome light on some compact vehicles
• Trunk light, glove compartment light, storage compartment light
• Side marker lights

Converting T10 to LED

T10 LEDs are one of the simplest and most popular modifications in car tuning. Advantages:

• Pure white light (4,000 to 6,500 K) — no more yellow halogen light
• 10× longer lifespan than standard halogen
• Negligible consumption — eases battery strain
• Available interior colors: white, blue, red, green, amber (depending on desired style)

Important: outdoors, the highway code requires white for parking lights and license plates. No blue or colored bulbs for exterior position lights.

Difference with W16W

The W16W is also a wedge-base bulb, similar but 16W (vs 5W for the T10). Slightly larger physical format — not interchangeable. The W16W is mainly used for reversing lights on recent vehicles.