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SWAN Sleeve for M16/M4/AR-15 Flat-Top Receivers 5.56mm - The SWAN® Sleeve provides a platform that is semi-permanent to the M16/AR-15. When installed to the A.R.M.S.® designed M16 A3 flat top receiver, the Sleeve height provides a patented flip up rear sight The rear sight provides an A2 type windage adjustment with a standard 250-500m range zero, via the front sight post. The SWAN® Sleeve protects the flat top receiver, providing dovetail protection bumpers along the entire length. The Sleeve is available in three lengths. The spring loaded rear sight is cleverly designed to repeat zero each time it is released by the easy to activate positive hold release lever, even with arctic mittens.
Extended Length - 5.56mm Length 8.460"