When I bought my Chevy Volt, it came with a short 25' charging cable that forced me to park my car up at the house (and my wife's car, which is not electric, behind me). It was inconvenient to have to pull her car out every morning before work. Now, with the availability of this robust 40’ cable, she can stay up close to the house and I can charge behind her. This is wonderful. My charging time, using the longer cable, has remained the same as it was with the 25’ cable – and the cable stays cool. I am confident in the product and grateful that it has become available. Note: I have the NEMA 15-5 (Standard 110V plug) on the end. From the electrical panel, I have a dedicated, high Amp, circuit with robust cable in conduit to a dedicated plug in the garage – into which this extension is plugged. I am confident in its safety.