Updated: Sep 2, 2019
"Highly flexible annealed 30 gauge bare copper conductors, insulated with an STW water-resistant jacket. Operating temperatures range from -40C to +90C (-40F to 194F). The 8 gauge, 3 conductors are rated at 250V, 50A. Coiled, boxed, and shrink wrap packaging available. Designed for indoor and outdoor heavy industrial use. These cords are flexible, durable, and manufactured to meet or exceed all UL and OSHA requirements. Made in the USA. Rugged jacket. Receptacle lights up when the cord is powered. Resists abrasion and water. Unbreakable, molded-on connectors. Every cord is tested. Contractor approved. Meets all UL & OSHA requirements" -HarrisWeldingSupplies
Official Website / Online Store; https://www.harrisweldingsupplies.com/direct-wire-8-3-25-foot-220-volt-extension-cord-made-in-the-usa/
Product Review; "There are a handful of manufacturers around the US that make home-use AC power cables, I have about one from each company - trying to keep them all in business. Imported versions will be cheaper, but will have significantly less attention to quality (as well as essentially removing currency from our country). These cables are thickly insulated - sure to hold up for many years. I you have cables in your home that aren't made from a US company (and you want to make a positive impact in the world) I'd say you've got some shopping to do !"