Subaru Brat Dome Light Bulb Size

Subaru Brat dome light bulbs utilize a DE3175, 57, or 257 bulb size for interior overhead lighting applications. The replacement chart covers vehicle production spanning 1980 to 1987 with corresponding bulb specifications.

The year-by-year compatibility chart below provides a quick reference to verify the correct bulb size for your vehicle.

Bulb Size by Year Range

Years	Bulb Size
1982-1987	DE3175
1981	57
1980	257

Bulb Specifications

Description	Bulb Size
ANSI standard (US & Canada). Festoon bulb, 31mm length, end-cap contacts. 12V.	DE3175
ANSI standard (US & Canada). Single-filament bulb with BA9s base. 12V, 1W.	57
ANSI standard (US & Canada). Festoon or BA9s base instrument bulb. 12V, 2W.	257

Other Locations

Additional Notes

The DE3175 is a festoon-type bulb measuring 31mm in length with end-cap contacts, operating at 12V. It is the dome light bulb used in the Subaru Brat across the 1982-1987 model years.
Festoon bulbs make contact at both ends of the bulb body rather than through a traditional bayonet or screw base, which means correct length is critical for a secure fit in the lamp holder.
The 1981 Subaru Brat uses a size 57 bulb, a single-filament type with a BA9s miniature bayonet base, rated at 12V and 1W.
The 1980 model uses a size 257 bulb, rated at 12V and 2W. The 257 is specified with either a festoon or BA9s base configuration, meaning the physical form can vary by manufacturer.
All three bulb types listed in these specifications conform to ANSI standards applicable in the United States and Canada.
The DE3175 and the 257 both belong to the festoon category, but they are not interchangeable. The DE3175 has a defined 31mm length and end-cap contacts, while the 257 carries a different wattage rating and may also be produced in a BA9s base form.
The size 57 and size 257 bulbs share the BA9s base type in their respective configurations, but their wattage differs, with the 57 rated at 1W and the 257 at 2W, making substitution between them inadvisable without confirming socket and circuit compatibility.