DoubleStar Shorty A-2/ Entry length Buffer Tube Black. 5in Entry-Length Rifle Buffer Tube is a shorter version of the original rifle buffer tube. It is designed to work with entry length stocks that require a shorter rifle profile buffer tube such as the ARFX-E and the AR-UL-E. Specifications for DoubleStar Shorty A-2/ Entry Length Rifle Buffer Tube: Manufacturer: DoubleStar Color: Black Finish: Hard Coat Anodize Fabric/Material: 6061 Aluminum Gun Type: Rifle Length: 7.47 in Diameter: 1.11 in Condition: New Package Contents: DoubleStar Shorty A-2/ Entry Length Rifle Buffer Tube DoubleStar AR381: Shorty A-2/ Entry length Buffer Tube Black