These wrenches have a quick release reversible lower jaw with a serrated side with extra hard teeth for pipe gripping, a strong handle and a phosphated corrosion resistant finish. The smooth adjusting action makes them fast and easy to use. Conform to: ISO 6787-1982, ASME B.107. 8M-1996, BS 6333-1995, DIN 3117-1988, JIS B4604-1976.