Area 419 Hellfire Thread And Taper Protector Black Nitride. Made from 6061-T6 aluminum to protect all of the critical features on the Universal Adapter If you have multiple Universal Adapters on other rifles this is a great way to protect the threads and taper surface from damage Specifications for Area 419 Hellfire Thread And Taper Protector: Manufacturer: Area 419 Color: Black Nitride Fabric/Material: Aluminum Country of Origin: USA Package Contents: Area 419 Hellfire Thread And Taper Protector Area 419 419BK-ADT-TP: Hellfire Thread And Taper Protector Black Nitride