Permatex Medium Strength Threadlocker Blue (6 mL) - 24200 is a medium strength thread locker that is designed to lock and seal threaded fasteners to prevent loosening due to vibration. It is ideal for fasteners up to 1/4 (6mm) in diameter and can be used on all metals, including passive substrates such as stainless steel, aluminum, and plated surfaces. It is resistant to oil, water, and most shop fluids and is removable with hand tools for easy disassembly.