White Label Armory AR-10/15 Castle Nut Five Pack Black. Precision-machined from steel and phosphate coated for added corrosion resistance these castle nuts ensure a reliable tight fit on all standard carbine buffer tubes. Each nut is properly notched for staking to maintain alignment during use. Proudly made in the USA this 5-pack is ideal for builders looking for durability and consistency across multiple AR15 or AR10 platforms. Specifications for White Label Armory AR-10/15 Castle Nut: Manufacturer: White Label Armory Gun Model: AR-15 Color: Black Features of White Label Armory AR15/AR10 Castle Nut: Includes 5 steel castle nuts Compatible with AR15 and AR10 platforms Fits all standard carbine buffer tubes Mil-spec dimensions Phosphate coated for corrosion resistance Properly notched for staking Secures buffer tube assembly 100 percent American made Package Contents: White Label Armory AR15/AR10 Castle Nut What firearm models does the manufacturer say White Label Armory AR-10/15 Castle Nut is compatible with? The manufacturer says that White Label Armory AR-10/15 Castle Nut is compatible with AR-15White Label Armory WLA-PAC-7004-05: AR-10/15 Castle Nut Five Pack Black