AC WORKS 1.5 ft. L14-30P Generator 4-Prong 30 Amp Plug to (4) NEMA 5-15/20R 20 Amp Household Female Connectors Adapter Cord L1430F520-018 - The Home Depot
30A Generator Inlet Box and Extension Cable Combo,NEMA L14-30 4Prong up to 8000W | eBay
Champion Power Equipment 25 ft. 30 Amp 240-Volt Generator Power Cord 48036 - The Home Depot
Champion Power Equipment 25-Foot 30-Amp 125/250-Volt Generator Extension Cord (L14-30P to four 5-20R) Thermoplastic Yellow in the Generator Accessories department at Lowes.com
25 ft. 30A 250V Generator Power Cord - Champion Power Equipment