The KTM 450 EXC-F Six Days headlight bulb uses an HS1 size for both high beam and low beam functions. The replacement chart covers 2019 to 2021 production years with corresponding bulb size specifications.
The year-by-year compatibility chart below provides a quick reference to verify the correct bulb size for your vehicle.
The KTM 450 EXC-F Six Days uses the HS1 bulb type for both high beam and low beam headlight positions across the 2019-2021 model years.
The HS1 is a dual-filament halogen bulb, meaning a single bulb unit contains two separate filaments to serve both high and low beam functions within one housing.
The HS1 operates at 12 volts with a 35W/35W output rating, where each wattage figure corresponds to one of the two filaments.
The HS1 uses a PX43t base, which is a bayonet-style fitting specific to motorcycle lighting applications and is not interchangeable with common automotive bulb bases such as H4 or H7.
The HS1 standard falls under ECE regulation, making it the accepted specification for motorcycle headlights in Europe and numerous other markets worldwide.
Because the same HS1 bulb type is specified for both the high beam and low beam positions, the 450 EXC-F Six Days headlight assembly relies on a single bulb rather than separate units for each function.