RV Power Cord Plug Adapter 15 Amp Male to 30 Amp Female With Twist Lock USA | eBay
AC WORKS NEMA 5-15P to NEMA 5-20R 15-Amp 3-wire Grounding Single To Single Black Basic Compact Adapter in the Adapters & Splitters department at Lowes.com
30 Amp Male to 15 Amp Female RV Pigtail Power Adapter
Amazon.com: Camco PowerGrip 30AM/15AF Camper/RV Electrical Adapter | Features 30-Amp Male & 15-Amp Female Connections | Designed w/Non-Slip Grooves & Contoured Ends for Easy Removal | Rated for 125V/1875W (55233) : Automotive