| Our Internal Pipe Wrenches are designed to rescue HVAC and plumbing professionals from broken pipe threads, plugs and fittings. The machined, heat-treated cams grab on to broken pipe fragments that have become lodged inside other pipe. The hex-shaped bodies are made from alloy steel and can be used with open- or closed-ended wrenches. Our Professional Series Wrenches conform to government specifications for size and weight. Set includes three wrenches.