Collection: Vintage & Classic Cars > Headlights & European Dip

Bulbs for classic cars: models often hard to find

Vintage vehicles (pre-1980, approximately) use non-standard bases that have become rare: P45t, P36d (sealed beam headlights), BA20d (motorcycles and microcars), S2, R2 (European Code). These formats have been abandoned from general public catalogs in favor of modern H4 and H7 bulbs — but they remain essential for maintaining classic vehicles. Pharos Boutique has kept this range in stock since 1962.

The “European Code”: what is it?

The European Code refers to the asymmetrical beam of light towards the right, designed for right-hand traffic in France and continental Europe. It gradually replaced the old symmetrical beams in the 1950s-1960s.

The asymmetry allows for illuminating further on the right side (the side of the road) without blinding oncoming drivers in the left lane. The P45t and R2 bases are the most common versions of the European Code on vintage French and European cars (Renault 4, 4CV, Dauphine, Peugeot 203/403, Citroën 2CV/DS, Simca Aronde).

H4, P45t, BA20d, S2, R2: a guide to old bulb bases

• H4 (P43t) — double filament low beam + high beam, appeared in 1971 (Beetle). Found on many classic cars from the 70s and 80s. Universal base — still referenced at Pharos.
• P45t / P36d — sealed beam headlights, European and American format. The glass, reflector, and filament form an inseparable unit — the entire assembly is replaced.
• R2 (European Code) — specific French base for the asymmetrical low beam. Available in white and yellow (vintage look).
• S2 — specific French base for old stop lights. Cars before 1965.
• BA20d — 20 mm bayonet base for headlights of old motorcycles (Solex, Mobylette, old mopeds), microcars, and some industrial lighting.

LED for classic cars: possible but with precautions

LED conversion is possible for certain classic car bulb bases — especially H4, for which CE-approved LED kits are available. For rarer bases (R2, P45t, BA20d), LEDs exist but are less common.

Important precaution: on vehicles with a dynamo (instead of a modern alternator), the voltage fluctuates with engine speed — check the electronic compatibility of the LED with your system. Some LEDs require a stable voltage regulator. It's best to test before final installation.