Geissele Suppressor Alignment Gage (SAG) | 15.5in 5.56mm

The Geissele Suppressor Alignment Gage (SAG) is a precision tool used to verify that a suppressor is concentric with the bore of a firearm barrel. Manufactured from hardened steel and finished to tight tolerances, the SAG helps reveal small deviations at the mounting interface that can magnify downrange. Its long length aligns to the bore, reducing the need for an extremely tight fit while providing a reliable reference for installation and inspection.

Common applications include gunsmithing or suppressor installation checks and routine maintenance inspections to detect baffle or mounting misalignment. The SAG is intended strictly as an alignment verification tool and not as a measuring caliper or bore-sizing instrument.

Product Specifications

• The product is identified as the Suppressor Alignment Gage (SAG).
• The overall length is 15.5 inches for long-range alignment to the bore.
• The listed target bore size is 5.56mm for compatibility with typical 5.56mm barrels.
• The gage body is made from hardened steel to resist wear and particle embedment.
• The outside diameter is ground to 0.002 inches under nominal bore diameter to fit most barrels while remaining functional along its length.
• The outside diameter is finished and straight to 0.001 inches over its length for precise alignment reference.
• The color/finish is specified as Black.
• The listed material is Steel.
• The product dimensions are 0.95 x 0.80 x 15.50 inches.
• The listed height is 0.9500 inches and the listed width is 0.8000 inches.
• The listing includes a Make/Model designation of AR-15.
• The design intent is described so that the 15.5-inch length aligns the gage to the bore and a very tight fit is not required.
• The gage is finished to resist sliding wear, pull burrs, and abrasive particle embedment by virtue of its hardened surface.
• Shipping restriction note on the original specification: No direct ship to California.
• The UPC is 854014005243.

The Geissele SAG provides a robust, precision reference for verifying suppressor-to-bore alignment during installation and maintenance. Its hardened construction and tight straightness tolerances make it suitable for professional and experienced amateur use where accurate alignment matters. The long length simplifies alignment checks without requiring a press-fit, and the finish has been optimized to withstand exposure to powder residue and contact with suppressor baffles.