Caterpillar-style premium aftermarket hexagonal bolt. Part reference 8T9311. Size/application: Hexagonal Head Bolt. Use a matching specified-thread high-strength nut; the exact nut reference is not listed in this catalog. General heavy-equipment fastening hardware for the matching assembly. Brand compatibility: Caterpillar and premium aftermarket systems built to the matching Caterpillar specification. Standardized dimensions may also fit other major brands when diameter, thread, length and seat are identical. Confirm strength grade, thread pitch and installed length.