Amazon.com: ACKING Heavy Duty 8 Guage 3 Prong Welding Power Extension Cord, NEMA 6-50P to 6-50R Welder Plug Outlet Extension Adapter, 50 amp 250v Heavy Duty Electric Extension Wire Generator,25FT Cord :
VEVOR RV Extension Cord 40 Amp 50 ft. 250V 8 AWG/3C Welder Power Cord with NEMA 6-50 Plug STW Jacket for Welding RV Generator HJLJQ8-3-50FTYCX1V1 - The Home Depot
Coleman Cable 19228806 8/3 Heavy-Duty STW 50-Amp/250-Volt Nema 6-50 Blue Welder Extension Cord, 50-Feet - Extension Cords - Amazon.com
iMeshbean® Welder Extension Power Cord 25/50 FT 220 Volt 50 Amp 8/3 NEMA 6-50P for MIG TIG Plasma Welding Heavy Duty (Welder Adapter 14-50P 50A 4-Prong Plug to 6-50R with Handle) - Amazon.com
Direct Wire & Cable - #8/3 Heavy Duty Welding Machine Extension Cord - RAM Welding Supply
parkworld 50 ft. 8/3 40 Amp 250-Volt Heavy-Duty NEMA 6-50 Welder Extension Cord 885330 - The Home Depot