Upgrade your AR-15 with industry-leading reliability and performance using the Geissele Reliability Enhancement Kit® H2 5.56 mm. Designed for 5.56 NATO rifles, this precision-engineered upgrade combines a Reliability Enhanced Bolt Carrier Group (REBCG) with a Super 42 braided-wire buffer spring and H2 buffer to deliver smoother cycling, reduced wear, and improved feeding consistency under a wide range of conditions. The full-mass, M16/M4-profile bolt carrier group is built from premium materials and finished with Geissele’s exclusive Nanoweapon® chrome-nitride coating — providing exceptional resistance to corrosion, wear, and abrasion while simplifying maintenance.

The included Geissele Stressproof® bolt is forged from Carpenter 158+ steel for enhanced strength and fatigue resistance, offering far greater longevity than standard mil-spec components. The extended upper rails on the carrier boost stability and increase feeding reliability, while the H2 buffer and Super 42 spring help mitigate felt recoil and promote smoother bolt carrier movement — especially beneficial for high-round counts and demanding defensive applications.

Whether you’re building a tactical rifle, defensive carbine, or high-performance AR-15, the Geissele Reliability Enhancement Kit® H2 delivers a significant upgrade in reliability, durability, and overall operational consistency.