Guntec USA AR-15 Gen 2 Mil-Spec Buffer Tube Set w/Notch Cut Out For Buffer Black. The flexibility of these AR15 Lower Parts makes the Guntec USA GUNTEC USA AR-15 Gen 2 Mil-Spec Buffer Tube Assembly Set a perfect choice for a standard-length buffer tube. Complete with an end plate castle nut 3 oz. CAR buffer and upgraded chrome silicon spring this full buffer tube assembly kit is ready to make your build easier and more enjoyable.Replacement end plates are also sold separately. Castle nut and end plate are not included with the GUNTEC USA AR-15 Gen 2 Mil-Spec Buffer Tube Assembly Kit. Specifications for Guntec USA AR-15 Gen 2 Mil-Spec Buffer Tube Assembly Set: Manufacturer: Guntec USA Color: Black Fabric/Material: T6 Aluminum Gun Make: AR Platform Gun Model: AR-15 Additional Features: w/Notch Cut Out For Buffer Features of Guntec USA AR-15 Gen 2 Mil-Spec Buffer Tube Assembly Set Mil-Spec Buffer Tube Kit Gen 2 Tube Design With Notch Cut Out For Buffer Detent To Engage End Plate Castle Nut 3 oz CAR Buffer & Upgraded Chrome Silicon Spring T6 Aluminum Six Position Buffer Tube Package Contents: Guntec USA AR-15 Gen 2 Mil-Spec Buffer Tube Assembly Set What firearm models does the manufacturer say Guntec USA AR-15 Gen 2 Mil-Spec Buffer Tube Assembly Set is compatible with? The manufacturer suggests that Guntec USA AR-15 Gen 2 Mil-Spec Buffer Tube Assembly Set is compatible with AR-15Guntec USA MILTUBESET-G2: AR-15 Gen 2 Mil-Spec Buffer Tube Set Black