Champion Power Equipment 30-Amp RV Generator 30-ft / 1 3-Prong Outdoor Heavy Duty Locking Extension Cord in the Extension Cords department at Lowes.com
10ft 30 Amp NEMA 10-30 3-Prong Dryer Extension Cord 30A 125/250V US | eBay
RV Extension Cord 30 Amp
Amazon.com: Cable Matters 3 Prong 30 AMP RV Extension Cord 25 ft (30 AMP RV Power Cord, 30 AMP Extension Cord) - 25 Feet (NEMA TT-30P to TT-30R) : Tools & Home Improvement
S7 25FT 30Amp NEMA 10-30P/10-30R 3 Prong Dryer Extension Cord with Heavy Duty Thick Anti-Weather Outdoor Extension Cord - Amazon.com
AC WORKS 50ft NEMA L6-30 Cord 50-ft 10 / 3-Prong Indoor/Outdoor Soow Heavy Duty Locking Extension Cord in the Extension Cords department at Lowes.com
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