Koito 12V 21/5W (W21/5W) Glass Base Bulb – No. 1891 – Genuine OEM Japan Quality

The Koito 12V 21/5W glass base bulb (manufacturer number 1891) is a genuine product of Koito Manufacturing Co., Ltd. – one of Japan’s leading OEM suppliers for Honda and Acura. This is a dual-filament W21/5W bulb, used for tail and stop lights. Known for its precise construction, consistent brightness and long lifespan, it represents the benchmark of OEM lighting quality in Japanese vehicles.

Replacement for Genuine Honda OEM Bulbs

The Koito 1891 bulb serves as a direct OEM replacement for factory-installed bulbs in many Honda and Acura models. It matches the following Honda OEM part numbers:

• 34906-S30-003
• 34906-S2K-003
• 34906-ST5-003
• 34906-ST5-003HE
• 34906-S5P-A01
• 33303-T7S-G01

Thanks to identical voltage, wattage and dimensions, the Koito 1891 bulb fits directly in place of the original OEM units without any modification.

Applications – Honda and Acura Models

The Koito 12V 21/5W bulb is used in a wide range of Honda and Acura vehicles equipped with tail/stop light sockets of the W21/5W type:

• Acura 2.5 TL (1995–1998)
• Acura 3.2 TL (1996–1998)
• Acura 3.5 RL (1996–2004)
• Acura RDX (2015)
• Honda Accord 2D (2008–2015)
• Honda Accord 4D (1995–2015)
• Honda Accord Coupe (1995–2002)
• Honda Accord Crosstour (2010–2012)
• Honda Accord Tourer (2003–2015)
• Honda Brio (2013–2016)
• Honda Brio Amaze (2014–2016)
• Honda City (2001–2008)
• Honda Civic 3D (2007–2011)
• Honda Civic 4D (1996–2016)
• Honda Civic 5D (2004–2011)
• Honda Civic Coupe (2001–2005)
• Honda Civic Hybrid (2003–2011)
• Honda CR-V (1997–2017)
• Honda Crosstour (2011–2015)
• Honda HR-V (1999–2005; 2016–2018)
• Honda FR-V (2005–2009)
• Honda Freed (2012)
• Honda Insight (2000–2005)
• Honda Jazz (2002–2011)
• Honda Legend 4D (1996–2004)
• Honda Logo 3D (1999–2000)
• Honda Mobilio (2015)
• Honda MR-V (2003–2008)
• Honda Odyssey (1995–2013)
• Honda Pilot (2009–2012)
• Honda Prelude (1997–2001)
• Honda Shuttle (1998–1999)
• Honda Stream (2001–2005)
• Honda S2000 (2000–2003)
• Honda Vigor (1995–1998)

Note: due to market and model variations, verifying the correct OEM part number by VIN is recommended before purchase.

Technical Data and Packaging Information

• Manufacturer: Koito Manufacturing Co., Ltd.
• Manufacturer part number: 1891
• Type: W21/5W dual-filament bulb
• Voltage: 12 V
• Power: 21/5 W
• Base type: glass
• Function: tail and brake (stop) light
• OEM quality – identical to original Honda bulbs
• Vibration and heat resistant
• ECE approved
• Bulk packaging: 10 pcs per box
• Sold individually (no retail packaging)

FAQ – Koito 12V 21/5W (W21/5W) Bulb

Is Koito an original OEM manufacturer?
Yes. Koito is one of the main OEM suppliers for Honda and Acura vehicles, producing lighting components used during factory assembly.

What are the technical specifications?
Type W21/5W, voltage 12 V, power 21/5 W, glass base, manufacturer number 1891. Fully compatible with Honda OEM bulbs.

How is the bulb packaged?
The bulbs come from Koito’s bulk packaging (10 pcs per box) and are sold individually without original retail boxes.

Will it fit my car?
In most cases, yes. However, please verify the correct OEM number by VIN before purchase to ensure proper fitment.