A.R.M.S.® Bi-Level S.I.R.® System

Fits flat-top equipped weapons with carbine length gas systems. The #50 is a slim line S.I.R. ® featuring a bi-level top dovetail rail. The forward rail section is lowered to allow co-witnessing of heads up display type optics when used in conjunction with our #40 series rear sights and a standard height front sight post. Installation requires the removal of the delta ring.
ARMS-50.M $369.99

Item Availability

• Free floating barrel design to achieve maximum accuracy potential. • Removable side and bottom dovetail rail panels for mounting accessories such as lights, lasers and vertical forward grips. • Drastically enhanced cooling. • Lightweight and rugged aluminum construction. • Quick Change Lower Handguard. • Available in both Civilian(C) and Military(M) configurations. (Installation of Military S.I.R. ® Variants requires removal of the Delta Ring/Handguard Retaining Ring). • The S.I.R. ® System is designed to fit mil-spec flat top receivers in the 5.56 cal. carbine, mid, and rifle lengths. The #51 S.I.R. ® Allows mounting to the carbine A1/A2 carry-handle. There may be other flat top receivers manufactured that the S.I.R. ® may fit to properly, but we do not guarantee or warranty the S.I.R. ® on any flat top receivers other than those listed above.
No additional information is currently available. If you have further questions, please call 800-367-3763 for Streicher's Customer Service.

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