In a previous review, Aaron Warner was seeking to remove some of the slop from his center belt with the use of this part. There are three options, one is to shim the Rear Bulkhead Bearing Housing, another to create a custom belt tensioner. I have found that using this part, along with the lower graphite deck removed all slop in my center belt completely. Furthermore, it is a beautifully machined part that certainly adds a bit of bling factor to the drift car. Not an essential upgrade, but it sure makes the car stand out!
When using higher grip tires with the D3 the default rear bulk head exhibits flex in the upper deck when performing initial acceleration, this causes the center belt to skip and wear faster unless you have the version 2 aluminium rear bulkhead installed.
I got this to try and minimize the flex.
After testing, this was found to flex exactly the same as the default hard plastic upper deck so it does not solve the problem.
But it is still a nice aesthetic upgrade. You need to make sure you position your ESC as far to the side of the chassis as possible as this is physically wider than the default plastic upper deck and may come in contact with the cooling fan of the ESC.