The two-piece structural locking mechanism seals 4 to 20-mm-diameter holes in steel, iron, and aluminum. The system installs high and low-pressure seals in 2 sec in engine blocks, cylinder heads, transmission components, brake systems, compressors, hydraulic blocks, and pumps. Avseal II eliminates preliminary processes such as reaming and tapping, extra sealant, and torque-controlled tools. Features include a zinc-plated steel mandrel crimped for easy installation with standard handheld tools and high-speed automation equipment, and a tapered plug stem for ease of entry into tooling equipment.