25Feet Generator Extension Cord NEMA L14-30P to Four 5-20R 4 Prong 10 Gauge | eBay
Houseables Generator Extension Cord, Electric Wire, 3 Prong, 30 Amp, 250 Volt, Single, Black, 25 Ft, All Rubber, 10 Gauge, Heavy Duty, L6-30, Commercial, Electrical Power Cable, with Locking Switch - Amazon.com
Champion Power Equipment 25-Foot 30-Amp 125/250-Volt Duplex-Style Flat Generator Extension Cord (L14-30P to Four 5-20R) - Thermoplastic - Yellow in the Generator Accessories department at Lowes.com
HZXVOGEN 25-Foot Heavy-Duty Generator Extension Cord, Generator Lock C
DEK 10/4 240V L14-30 Universal Generator Cord G08510 - The Home Depot