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Big Gun ATV TFI power boxes are neat and compact accessories that add a big advantage once installed into your ATV. Known to actively amplify horsepower and throttle, they are easily installed in a matter of minutes. Big Gun ATV TFI power boxes are engineered as the new third generation of Big Gun technology, they are easy to adjust and utilize the plug-in expertise which supports the stock ECU mapping system. Big Gun ATV TFI power boxes require no computer to adjust the EFI and make use of integrated faceplate buttons to provide easy alteration.