Knob-and-tube wiring remains one of the most common legacy electrical systems found in older homes across the United States, particularly in regions with historic housing stock such as Massachusetts, New York, Pennsylvania, and parts of the Midwest. Installed from the 1880s through the early 1930s , this wiring method represented state-of-the-art technology for its time. Today, however, it presents a number of safety, insurance, and usability concerns that homeowners must und