The Best P21 4W Bulb of 2025 – Reviewed and Top Rated
After hours researching and comparing all models on the market, we find out the Best P21 4W Bulb of 2025. Check our ranking below.
2,503 Reviews Scanned
Rank No. #1
Eluseastar S25 P21/4W BAZ15D LED Bulbs White 6000K Built in Resistor with 6000LM Extremely Bright for Car Side Marker Brake Reverse Backup Daytime Running Light, 2 Pack
- 【500%+ Brightness】: Pack of 2 BAZ15D(P21/4W) led bulbs come with 2A current, 6000K Pure White, Voltage: DC 12V-24V, Power: 25W/PC, 5000LM 5 times brighter than the halogen.
- 【Fits】: S25 BAZ15D P21/4W etc. Easy installation, plug and play in 90% cars in the world.
- 【CANBUS Error Free】: Built in Intelligent Constant IC Driver: 2A real current consumption-strongest Canbus function; Canbus error free in most of cars. High power version led bulb.
- 【Application】: For Back Up Reverse Lights, Brake Lights, Tail Lights, Parking Lights, Side Marker Lights, Daytime Running Lights etc. . It is the same socket as the P21/4W socket,you can use it with confidence if it is a [P21/4W] socket model of your car original halogen bulb,Plug and Play.
- 【Troubleshooting】: Some customers installed the bulbs in cars that originally used halogen bulbs. The On-Board Computer (OBC) of the car requires the power of halogen bulbs. When they install LED bulbs, the OBC will recognize the bulbs as incorrect, so after a while, it will not allow electricity to pass through the bulbs, causing the bulbs to turn on first and then turn off(Hyper flashes). To solve this problem for these special cars, customers need to add an (P21/4W) LED decoder.
Rank No. #2
Small Stones 4PCS 1157NA BAZ15D S25 12V P21/4W Halogen bulb Automotive Brake lights Tail lights Daytime running lights (Amber, BAZ15D)
- Category: Halogen lamp; Model: 1157NA/BAZ15D-12V P21/4W.
- Bulb height: 47 mm/1.85 in.
- Voltage: 12V; Power: 21/4W.
- This product is suitable for Automotive Brake lights, Tail lights, Daytime running lights.Easy installation, plug and play!
- Before purchasing an item, please check with the above parameters!
Rank No. #3
ALKOREY 1157 P21/5w Bay15d 12v 21/5w Light Bulbs,Backup Reverse Signal Blinker Tail Parking Brake Lights,2700K Taillight Turn Signal Light,2 Pack
- Product Specifications: ALKOREY provides 2 1157 warm white high-quality bulbs to meet your replacement needs. Taillights are all warm white bulbs with a color temperature of 2700K. All bulbs are produced according to strict testing requirements. You know this is a brand you can trust.
- High quality: These taillights are made of high temperature resistant and sturdy material, and are not easy to break during use. After lighting up, it is warm white light with high light transmittance, which can provide brighter and more comfortable light. Even when driving in rainy and foggy weather, it can well indicate the driving status without flashing, glare and other problems, escorting your safe driving.
- Easy to Use: The bulbs do not need to canbus and are easy to installed. You can directly replace it. The tail light will work immediately without waiting. All the bulbs are ROHS certificated, fully meet the requirements of the United States-safely and stable.
- Safe Driving: This bulb will not produce excessive glare or cause interference to oncoming drivers. It has wider illumination range and greater light intensity and can effectively expand the field of view in front of the vehicle, greatly improving driving safety and comfort. Avoid risks on the road ahead in advance and improve driving safety.
- Versatile Applications: High-quality bulbs have a wide range of applications and can be used as signal bulbs, taillight bulbs, side marker bulbs, brake bulbs, and more! Miniature bulbs are manufactured to meet precise lighting requirements and can meet a variety of brake light, stop light, turn signal, and reverse light applications.
Rank No. #4
Osram P21/4W 21/4W 7225-2BL
- OSRAM Bulb, brake light/tail light
- Compatible with BMW 3 Saloon (E46), Compatible with VW Polo IV 3/5 doors (9N, 9A), Compatible with BMW 3 Coupe (E46), Compatible with MERCEDES-BENZ C-Class Saloon (W203), Compatible with BMW 3 Touring (E46), Compatible with BMW 3 Saloon (E36), Compatible with Renault Megane III 3/5 doors (BZ0/1), Compatible with Skoda Octet Avia II Combi (1Z5)
- Please choose your vehicle from the drop-down list to check compatibility with the product.
Rank No. #5
SOCAL-LED LIGHTING 1157 BAY15d Green LED Turn Signal Bulb Advanced 3030 SMD Bright Colorful DRL Brake Lamp Parking Tail Light, Pack of 2
- LED Turn Signal bulbs powered by 12 High Power Efficient 3030 SMD chip, super bright in small size. Ideal for Side Marker, Tail Light or DRL with Colorful option.
- Super Bright Design Car LED bulb 280 Degree full Angle Illumination, new advanced 3D 3030 SMD emitter to achieve the Maximum Lighting Output.
- Alluminum Alloy Housing helps keeping it at a low working temperature, avoid damaging plastic parts around.
- Directly plug and play for most vehicles,easy installation. Yet for some European vehicles built in CAN-BUS system, it may require the load resistor or decoder to avoid the error code or blinking issues. DOES NOT COMPATIBLE WITH CK SOCKET!
- Cross Reference Number: BAY15d P21/4W 888 1016 1034 1076 1130 1154 1157 1158 1493 2057 2357 2397 7528; used for Brake Lights, Tail Lights, Back up Reverse Light, Center High Mount Stop Lights (3rd brake), Turn Signal Lights, or Parking Lights.
Rank No. #6
Eluseastar S25 BAZ15D P21/4W LED Bulbs White 6000K with Cooling Fan Extremely Bright for Car DRL Backup Reverse Tail Brake Light, 2 Pack
- ▼(Set of 2 Bulbs) 24pcs SMD2020 high brightness chips per bulb, built in 25w high power canbus error free on most of cars; Working Voltage: 12v-24v; Size: 1.95(inch)/49.45(mm) * 0.78(inch)/20(mm)
- ▼Advantage: Non-polarity design, Compatible for both CK/SRCK and Standard socket. More than 300% brighter than original halogen bulb, full Aluminum Housing for Maximum Light output and better heat distribution, built in Constant Current IC with Cooling fan for Longer life span & Low Power Consumption.
- ▼High Lumen: 5000LM Extremely bright white color, +300% brighter than stock bulb. lighting output,color: white
- ▼Easy to install: Built in Canbus error free in 95% cars, just simply plug and play; Please double check owners manual or original bulb number to confirm before placing an order. Any other problem please feel free to contact us, we are always here to satisfy of you.
- ▼Fit in most BAZ15D P21/4W S25 etc socket. Can be used for back up/reverse lights, brake/tail lights, turn signal/parking or daytime running Lights, blinker lights, side marker lights, DRL etc.
Rank No. #7
Eluseasta S25 BAZ15D P21/4W LED Bulbs White 6000K with Cooling Fan Extremely Bright for Car DRL Backup Reverse Tail Brake Light, 2 Pack
- ▼(Set of 2 Bulbs) 24pcs SMD2020 high brightness chips per bulb, built in 25w high power canbus error free on most of cars; Working Voltage: 12v-24v; Size: 1.95(inch)/49.45(mm) * 0.78(inch)/20(mm)
- ▼Advantage: Non-polarity design, Compatible for both CK/SRCK and Standard socket. More than 300% brighter than original halogen bulb, full Aluminum Housing for Maximum Light output and better heat distribution, built in Constant Current IC with Cooling fan for Longer life span & Low Power Consumption.
- ▼High Lumen: 5000LM Extremely bright white color, +300% brighter than stock bulb. lighting output,color: white
- ▼Easy to install: Built in Canbus error free in 95% cars, just simply plug and play; Please double check owners manual or original bulb number to confirm before placing an order. Any other problem please feel free to contact us, we are always here to satisfy of you.
- ▼Fit in most BAZ15D P21/4W S25 etc socket. Can be used for back up/reverse lights, brake/tail lights, turn signal/parking or daytime running Lights, blinker lights, side marker lights, DRL etc.
Rank No. #8
in.pro. Light Bulb P21/4W Blister Pack of 2
- Branded product
- P21/4W
- ECE approved
- Light bulb
- Brand new
Rank No. #9
Eluseastar S25 BAZ15D P21/4W LED Bulbs White 6000K Built in Resistor with 48LED-SMD4014 Chip Extremely Bright for Car Side Marker Daytime Running Brake Tail Light, 2 Pack
- 【300%+ Brightness】: Pack of 2 P21/4W led bulbs, white color lighting output, Voltage: DC 12V-24V, Power: 20W/PC, 5000LM 3 times brighter than the halogen.
- 【48 pcs SMD4014 chipset】: There are 48 pcs SMD4014 chips buit in each bulb, more brighter than halogen bulb.
- 【Fits】: S25 BAZ15D P21/4W etc.
- 【CANBUS】: Built in Intelligent Constant IC Driver, consumption-strongest Canbus function; Canbus error free in most of 90% cars. High power version led bulb.
- 【Application】: For Brake Lights, Tail Lights. It is the same socket as the P21/4W socket,you can use it with confidence if it is a P21/4W socket model of your car original halogen bulb, Just Plug and Play.
Rank No. #10
in.pro. Light Bulb P21/4W Blister Box Pack of 1
- Branded product
- P21/4W
- ECE approved
- Light bulb
- Brand new
Last update on 2026-07-01 / Affiliate links / Images from Amazon Product Advertising API
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