Collection: H21W / HY21W / WY21W Bulbs

H21W, WY21W, and HY21W: Amber Glass Turn Signals

These bulbs are distinguished by their integrated orange/amber tinted glass — the regulatory color for turn signals is produced by the bulb itself, not by an orange plastic filter in the light assembly. This is the preferred solution for premium vehicles with clear turn signal lenses that require a colored bulb to comply with regulations.

Typical vehicles: certain BMW (3 Series, 5 Series), Mercedes (C-Class), Volvo (S60, V70), certain recent Renault and Peugeot models.

H21W, WY21W, HY21W: What's the difference?

Three variants based on the mechanical base:

• H21W — BAW15S base (metal bayonet). Older format, found on vehicles from the 2000s.
• WY21W — W3×16d (plastic) base. Modern format — the orange variant (the "Y") of the white W21W. Equips recent vehicles.
• HY21W — variant with a slightly different base depending on the manufacturer.

It is essential to check the exact type on the original bulb or in the manual — these bases are not interchangeable despite having an identical function.

LED for H21W and WY21W

Replacement orange LEDs exist for these bases. For turn signals, the orange color must be maintained — choose an LED with orange emission or tinted glass.

Important precaution: check CANbus compatibility. Premium vehicles (BMW, Mercedes) are often equipped with control units sensitive to consumption variations — a non-CANbus LED can trigger a fault light and systematic hyperflashing.