I recently connected my house with CAT6 points in every room. However, when I connected the device to the router, I could not connect to the network. With this simple tool, I quickly found myself swapping out two pairs in a trapezoidal socket in the wall. It was easier to fix at the router by rewiring the new RJ45 connectors. Also found 2 broken wires/bad crimps. It's a simple little tool, but it comes in very handy when troubleshooting wiring problems. The only improvement I would make is to slow it down. Even in slow mode, it iterates through the rows fairly quickly.