Spikes Tactical Ejection Port Door - .308. 308 ejection port door to build out your stripped .308 upper. NOTE: Jack10 and Livewire sets already have the door installed. Specifications for Spikes Tactical Ejection Port Door - .308: Manufacturer: Spikes Tactical Color: Black Caliber: .308 Winchester Country of Origin: USA Features of Spikes Tactical Ejection Port Door - .308: Works with .308 upper receivers Door Constructed from Stamped Steel Mil-Spec Heavy Phosphate Coating Weight: .53oz Package Contents: Spikes Tactical Ejection Port Door - .308 Spikes Tactical SEDX700: Ejection Port Door - .308