Review on ⚡ Upgrade Your EV Charging Experience: BESENERGY J1772 Extension Cable, 40Amp 220V-240V Charging Cord for Electric Vehicles, 20ft 6m Length, Compatible with All SAE J1772 Chargers by Kevin Harmon

EDIT: DO NOT BUY. 1.5 years of use and the J1772 connector will become *HOT* with use. My OpenEVSE keeps turning on and off because the port can't even handle 30A. After an hour of charging, my J1772 port is 84C, which is *MUCH* too hot. J1772 cannot be opened for inspection/repair. So I lost $100 on a new plug. I bought a 40A cable and it *didn't* disappoint. I bought this extension to use with OpenEVSE, so I had the pleasure of snapping the cable right away for almost $200 :-) This cable is *extremely* durable and has a wire diameter of 3.8mm. It's actually a slightly larger 7ga wire (they document 8ga). As indicated in the documents, the wire is made entirely of copper. The J1772 receiver connector is crimped tightly and each individual pin has an internal seal to prevent water from entering the connector. The pins are well crimped onto the wires. The cable entries are strong and well sealed. The total cable diameter of 40A is 15.5mm.