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
10/3 AWG NEMA TT-30 30 Amp Generator Extension Power Cord – GearIT
25' Black 10/3 30A RV Extension Cord - Pleasure Land RV Surplus Store
Amazon.com: Camco PowerGrip 30-Amp Camper/male RV Extension Cord | Features a Durable Heat-Resistant PVC Construction with 10-Gauge Wires and a Flexible Design | Rated for 125 Volts/3750 Watts | 25-Feet (55191) : Automotive