PWS offers 3 different buffer tubes: The Enhanced Buffer Tube, Enhanced Pistol Buffer Tube, and the Modified Enhanced Buffer Tube. 

The Enhanced Buffer Tube features 6 settings for adjusting a stock or pistol brace. The SBA3, or other adjustable braces, require this buffer tube to be able to adjust the brace. Adjustable stocks also require this buffer tube. This buffer tube is not A2 length. At this time, PWS does not make an A2 length buffer tube. 

The Enhanced Pistol Buffer Tube is completely round, and does not have any type of settings for adjusting a brace. This buffer tube comes standard on our complete pistol builds and pistol lowers. The Pistol Storage Device, KAK Shockwave brace and other "set it & forget it" not as easy to adjust braces require this buffer tube 

The Modified Enhanced Buffer Tube does not have the extended anti-tilt lips. This buffer tube should be used if you are using the Law Tactical Folding Adapter, or with our MK2 lower. Our MK2 lower has anti-tilt lips machined into the lower, so it does not require the extended lips that are present on the standard Enhanced Buffer Tube.

Below is a photo of the Enhanced Pistol Buffer Tube and Enhanced Buffer Tube for reference.