As we know, there are numerous manufacturers of attachments/body kits and also made of a wide variety of materials such as Aluminum, carbon or GFK. But these components are often delivered without any certificates. And usually the manufacturers are not very well known. As a rule of thumb, you can say: components from well-known manufacturers are easier to register, as they usually have a visible marking, such as the manufacturer Seibon Carbon. Various Chinese components or any no-name parts without documentation are generally unrecorded, unless there is at least one Material report, in order to be able to prove how stable and from which material the new body part is. And of course, the parts must also be properly installed on the vehicle.
Topic: carbon hood
Especially the popular ones Carbon hoods are rarely provided with a certificate. However, if there is a carbon hood ex works for the desired vehicle type (e.g. in the case of the BMW M5 CS), then this can usually also be legally installed on the normal M5 (F90) or on the 5 Series (G30/G31). Nevertheless, one should also here previously consult with a testing organization and the manufacturer. Alternatively, if the hood is of high quality and comes with a material certificate, then registration is of course also possible in this case without any problems. An example is carbon hoods from BMW tuner Hamann Motorsport. However, these do not cost around €1.000 like the ones from eBay, but can easily cost +€8.000.
Important to note: If the bonnet has only one middle lock, then you must necessarily so-called Aero catches obstruct. If the bonnet also has lateral latches, then you do not need aero catches. The side locks have the same stabilizing effect as the Aero Catches and are sufficient.
Front skirts & rear skirts
In general, it also applies here that the aprons must have the manufacturer embossed or a proof of strength must exist. At best, the manufacturer should also be well-known here and the apron should not be a no-name part from a large auction house. Here, too, the component must be fitted precisely and sensibly before acceptance.
new fenders
Carbon/GRP fenders must meet the same guidelines as Front skirts & rear skirts from the accessories. If you want to install fenders such as those from the well-known "Liberty Walk" body kits, then you have to make sure that stone chip protection in the form of "body cloths" has to be installed. This is mandatory! This is to ensure that neither your own nor other vehicles are damaged/disrupted by stones/dirt flying around from the tyres. And seen from above, the tire must be covered by the fender to ensure successful entry. And without documents also here: No way!
