Suzuki Motorcycle LT-A400F KingQuad AS/ASi Tail Light Bulb Size

Suzuki Motorcycle LT-A400F KingQuad AS/ASi tail light requires a P21/5W bulb size. The replacement chart covers vehicle production spanning 2008 to 2019.

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	US Type	EU Type	Shop
2008-2019	1157	P21/5W	Check Price

Bulb Specifications

Description	Type	Shop
ECE standard (Europe & worldwide). Dual-filament signalling bulb with BAY15d bayonet base. 12V, 21W/5W.	P21/5W	Check Price
ANSI standard (US & Canada). Dual-filament bulb with BAY15d bayonet base. 12V, 21W/5W.	1157	Check Price

Other Locations

Additional Notes

The Suzuki LT-A400F KingQuad AS/ASi uses the P21/5W bulb for its tail light across the 2008-2019 model years.
The P21/5W is a dual-filament bulb, meaning it contains two separate filaments within a single glass envelope. The higher 21W filament serves the brake light function, while the lower 5W filament handles the running light function.
The P21/5W operates on a 12V electrical system, which is standard for most powersports and automotive lighting applications.
The bulb uses a BAY15d bayonet base. This base type features two offset pins at different heights, a design that prevents incorrect installation by ensuring the bulb can only be seated in one orientation, keeping the two filaments correctly aligned with their intended circuits.
The P21/5W is manufactured to ECE (Economic Commission for Europe) standards, a regulatory framework recognized across Europe and numerous other markets worldwide.
Because the BAY15d base is offset, it is not interchangeable with the BAY15s base, which is a single-filament bayonet fitting with symmetrically placed pins. Substituting a single-filament BAY15s bulb would result in incorrect circuit function.