FDL12
FDL12 is a designation used for a specific type of firearm component. It is most commonly associated with the AR-15 platform, a popular semi-automatic rifle. The "FDL" likely stands for "Forward Dust Cover" or a similar descriptor, indicating its function. The "12" may refer to a specific model number, generation, or a particular manufacturer's iteration of this component.
The forward dust cover, in general, is a small, spring-loaded metal flap that covers the forward assist
FDL12, as a specific product, might be produced by an aftermarket manufacturer and offered as an upgrade