Thompson Center Arms Cross-Slot Base engineered strictly for T/C Encore 12-Gauge shotgun barrels. Crafted from lightweight structural aluminum with a matte black anodized coating, this one-piece base features a cross-slot rail interface compatible with standard Weaver-style and most Picatinny rings. It mounts directly to factory drilled-and-tapped barrel holes using a secure 4-screw layout and supports up to a 25 in-lbs torque limit. Safety Note Always ensure the firearm is unloaded before installing or adjusting any optics or bases. Verify proper torque specifications during installation. Improper mounting may affect accuracy and safety.