Weaver #55 Ia Mark X (20a)

The Weaver #55 Ia Mark X (20a) scope base represents the gold standard in rifle optic mounting solutions for serious shooters, law enforcement, and military personnel. This precision-engineered base serves as the critical interface between your firearm's receiver and tactical optic system, ensuring zero shift, repeatability, and rock-solid performance in the field. Whether you're building a duty rifle, competition platform, or precision rifle, the Weaver #55 Ia Mark X delivers the reliability and accuracy that professionals depend on when mission success is non-negotiable.

Engineered with Weaver's proprietary Ia-format dovetail geometry, this scope base features precision-machined surfaces that create a repeatable, secure seating surface for compatible scope rings and mounts. The Mark X (20a) variant is optimized for modern tactical applications, providing robust clamping surfaces with minimal tolerance stack while maintaining compatibility with standard Weaver ring systems. The compact 1 x 0.5 x 1.5-inch footprint and lightweight 0.06 lb design minimize point-of-aim shift and add negligible weight to your rifle platform, critical factors in long-range accuracy and field deployment scenarios.

This base is ideally suited for AR-platform rifles, precision bolt-action systems, and tactical carbines that require a low-profile, high-strength mounting solution. Installation requires proper receiver alignment and torque specifications—professional gunsmiths and experienced builders should verify compatibility with your specific rifle model and ensure correct ring-to-base engagement. The Weaver #55 Ia Mark X (20a) is the choice for operators who refuse to compromise on mounting stability, whether in training, competition, or duty environments where zero retention is mission-critical.