Chevrolet Chevelle Radio Display Bulb Size

The Chevrolet Chevelle radio display utilizes 1816 and 1893 bulb sizes for illumination. Available information covers the period from 1964 through 1973 for the specified components.

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 Type	Shop
1973	1816	Check Price
1964-1972	1893	Check Price

Bulb Specifications

Description	Type	Shop
ANSI standard (US & Canada). Miniature wedge bulb (T3.25). 12V, 4W.	1816	Check Price
ANSI standard (US & Canada). Miniature wedge bulb (T5). 12V, 2W.	1893	Check Price

Other Locations

Additional Notes

The 1893 bulb is the radio display bulb specified for the Chevrolet Chevelle across 1964-1972, making it the dominant fitment across this application.
The 1893 is an ANSI-standard miniature wedge bulb rated at 12V and 2W, with a T5 envelope designation indicating its tubular glass shape is approximately 5/8 of an inch wide.
The 1816 bulb is specified for the 1973 Chevelle radio display, representing a distinct fitment from all prior model years in this range.
The 1816 is an ANSI-standard miniature wedge bulb rated at 12V and 4W, with a T3.25 envelope, making it physically smaller in profile than the 1893 despite its higher wattage rating.
Both the 1816 and 1893 share the same 12V operating voltage, but their wattage ratings differ by a factor of two, meaning the 1816 draws twice the current of the 1893 under normal operating conditions.
The wedge base design used by both bulb types relies on the glass envelope itself to make electrical contact, with no separate metal base or bayonet pins involved in the fitment.
Both bulbs carry ANSI standardization applicable to the US and Canadian markets, indicating conformance to a shared North American specification rather than a proprietary or regional-only standard.
The 1816 and 1893 are not interchangeable. The difference in envelope size (T3.25 versus T5) and wattage (4W versus 2W) means substituting one for the other risks either a physical fitment mismatch or an incorrect electrical load on the circuit.