The Mil-Spec 7075-T6 aircraft aluminum Anti-tilt Buffer Tube uses "carrier cradle" extensions to ensure that the carrier is always supported by the buffer tube, even when the bolt is forward. This prevents carrier-tilt and premature wear on the buffer tube. Thusly, the buffer-detent button doulbles as a lock that stops the buffer tube from rotating and becoming loose under extreme operation conditions. POF's desigin also features three (3) extra drain holes for marine environments.
AR-15, Issue:11, Page:048
Big Book Catalog, Issue:69, Page:047
SPECS: Mil-Spec, Six position, Black anodized, 3 drain holes