9. Then the counter gear was installed onto the counter boss nut and fit with the two provided break off keys (arrows) after aligning the grooves on the counter gear with the counter boss (shown here, the top key is already installed). With red threadlocker, Jason installed the bolt and washer to the counter boss nut and tightened it. The biggest safety feature of the Reverse Gear is the break-off keys. These brass keys are put in place to prevent damage to vital transmission components when the Reverse Gear is misused due to excessive load (i.e a reverse burnout).