Each specific adapter is specially made for the corresponding motorcycle model to ensure the best possible fit. These adapters are made of PVC or stainless steel. Technopolymer / PVC or stainless steel. To fit the indicators, these adapters are required. Note By purchasing the Rizoma License plate support, you may not need to buy the Rizoma rear turn signal mounting kit, too. In most cases, the License plate support kit includes the rear turn signal adapters. Therefore, it's always recommended to check the Rizoma license plate support technical info to verify the kit contains the brackets for Rizoma rear turn signals.