Big Gun Exhaust Rev Box 13500-13750 - 40-R12

Big Gun

  • $139.04
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If you are looking to swap out your stock CDI box, the Big Gun Rev Box is an affordable alternative to highly-priced OEM replacement boxes. It increases the overall RPM limit over the stock box and advances the timing curve. The Big Gun Rev Box is offered for various offroad MX and ATV models.


  • Increases overall RPM limit
  • Advanced timing curve
  • Easy direct plug in replacement to stock CDI box
  • 6 month Limited Warranty


  • 2004 Kawasaki KX 250F
  • 2004 Suzuki RM-Z 250

Brand: Big Gun Exhaust
Part Number: 40-R12

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