Collection: Old Bases (P45t, BA20d...)

Rare but still essential bulb bases

Before the progressive standardization around H4 and H7 in the 1980s, the European and American automotive industry used a wide variety of bulb bases, with each manufacturer having its preferences. Today, these bulb bases have disappeared from general public catalogs—Norauto, Feu Vert, or supermarkets no longer stock them. But they remain necessary for:

• The maintenance of vintage vehicles (pre-1980)
• The restoration of vintage motorcycles
• The maintenance of popular French cars (Citroën 2CV, DS, Renault 4, Peugeot 404, etc.)
• Certain old industrial vehicles and agricultural equipment

P45t and P36d: American and European sealed beams

The "sealed beam" format was the standard in the United States and on some European vehicles until the 1970s. The headlight glass and the bulb form an inseparable unit—the entire assembly is replaced as a single piece. The P45t (3-lug base) and the P36d (2-contact base) are the main references for these original headlights.

S2 and R2: Headlights for vintage French cars

The S2 (Stop, dipped/main beam) and the R2 (main beam) are specifically French designations that massively equipped Citroën 2CV, DS, Ami 6 and 8, Renault 4, 4L, 12 and 16, Peugeot 203, 404, 504. The R2, known as "European Code," were standardized in the 1960s across the entire European fleet.

Pharos references these bulbs in modern white and vintage yellow versions—yellow lighting was mandatory in France until 1993, and many collectors wish to preserve the original look.

BA20d, BA21d, BA20s: old bayonet bases

The old bayonet family includes several distinct diameters from the standard BA15s:

• BA20d (20 mm diameter, double filament) — headlights for old motorcycles (Solex, Mobylette, pre-1970 motorcycles), headlights for microcars.
• BA21d (21 mm) — signal lights on some European cars from the 1950s-60s.
• BA20s (20 mm, single filament) — motorcycle and vintage car ambient lighting.

These bases are not interchangeable with the modern BA15S—the difference in diameter (15 vs 20-21 mm) prevents any cross-mounting. An advantage for restoration: keeping the original bulb guarantees the authenticity of the vintage vehicle.