These crimp terminals feature an ultra-low profile design made from both conductive crimp metal and insulating plastic. A very easy duty. I was renovating the overhead lights in my RV and had to replace the spring clamps over the lights along the rows of lights, when I finished the light didn't work. I removed all the headlights, found a clamp that broke and replaced it. When I reinstalled all the bulbs, another crimp connector fell apart. Corrected that too. Then, two weekends after we drove the pickup truck to Florida, the string of lights was interrupted. Came home, pulled out all the lights and replaced those crimp connectors with crimp connectors from the local utility. These things are very, very light, they don't even stand up to targeted stress because they're almost completely useless. They're probably fine for repairing small gauge wire, maybe small battery operated devices and children's toys, but they just can't be trusted to protect thicker wire, maybe 20-22 gauge. Avoid