NGK B4ES Standard Spark Plug (4129)
Original price was: £7.85.£3.78Current price is: £3.78.
NGK B4ES Spark Plug – Stock No. 4129
A reliable, hot heat-range, non-resistor spark plug for classic and small-capacity engines that specify a 14 mm long-reach gasket-seat plug. Designed for steady ignition performance and easy starting.
- Nickel alloy centre electrode with copper core for consistent spark
- Non-resistor design for a strong spark signal
- Long 19 mm reach with gasket seat for common classic fitments
- Built to NGK standards for durability and fouling resistance
Important: This is a non-resistor plug. If you experience radio interference or your vehicle uses sensitive electronics, choose an NGK R-type equivalent if specified by the manufacturer.
Fitment guidance
Commonly used in classic cars, motorcycles, marine and small engines that require a 14 mm, 19 mm reach, non-projected, non-resistor plug in a hot heat range. Always confirm with our vehicle lookup or the Vehicle Fitment tab and your owner’s manual.
Technical specifications
| Part number | NGK B4ES |
| Stock number | 4129 |
| GTIN | 087295141298 |
| Category | 686 – Spark Plug |
| Thread diameter | 14 mm |
| Thread reach | 19 mm |
| Hex size | 20.8 mm |
| Seat type | Flat seat with gasket |
| Heat range | 4 (hot) |
| Resistor | No |
| Projection | Non-projected tip |
| Centre electrode | Nickel alloy with copper core |
| Ground electrode | Standard single ground |
| Factory gap | Approx. 0.7 mm (check and set to OE spec) |
| Tightening | Install to manufacturer torque spec. For new gasket plugs, typically 1/2 turn after finger-tight if torque data unavailable. |
Why it matters
A correct heat range and reach help prevent fouling and pre-ignition. The B4ES delivers a clean, reliable spark for smoother idle and dependable starts when specified for your engine.
The price displayed is for a single plug, please add the desired amount to your basket.
| Weight | 0.05 kg |
|---|---|
| Dimensions | 10 × 3 × 3 cm |
| Brand |
NGK-4129 Confirmed Fitment
Please note, this information is a combination of supplier provided compatibility data and our workshop expertise. While every effort has been made to ensure the accuracy of this information Progressive Parts Ltd are not liable for abnormalities or inaccurate data. Customers are wholly responsible for checking fitment for their vehicle. More information is available from our Terms & Conditions
UK Shipping
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DELIVERY INFORMATION
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DELIVERY INFORMATION
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Stock at Progressive Parts
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