Fortis Manufacturing Standard QD End Plate and Castle Nut Combo Black QD END-CN-COMBO. This AR15 lower receiver end plate is designed for carbine style buffer tubes for the AR15 and 308 platforms. The Fortis Standard Castle Nut is manufactured from a solid piece of billet aircraft grade aluminum that offers a significant weight reduction to ycastle nut. If you're trying to save ounces this is a great way but without sacrificing durability. The castle nut will fit onto mil-spec buffer tubes and quickly upgrade the form and function of ybuild. Specifications for Fortis Manufacturing Standard QD End Plate and Castle Nut Combo: Manufacturer: Fortis Manufacturing Color: Black Finish: Milspec Anodized Fabric/Material: 6061 Aluminum/Aircraft Grade 7075-T6 Aluminum Hand: Ambidextrous Gun Make: AR Platform Gun Model: AR-15 Quantity: 1 Features of Fortis Manufacturing Standard QD End Plate and Castle Nut Combo Fully radiused edges inside and out to prevent fraying of ysling Quick Detach Socket 1 1/4 Sling Loop You will need a standard stock wrench to install Package Contents: Fortis Manufacturing Standard QD End Plate and Castle Nut Combo What firearm models does the manufacturer say Fortis Manufacturing Standard QD End Plate and Castle Nut Combo is compatible with? The manufacturer says that Fortis Manufacturing Standard QD End Plate and Castle Nut Combo is compatible with AR-15Fortis Manufacturing QD END-CN-COMBO: Standard QD End Plate and Castle Nut Combo Black