Parkworld 885989 Welding Adapter cord L6-30 Plug 3-Prong 30A Locking Male to Dryer 14-30 Receptacle 30 AMP Female (Only For 125V, Two Hots pole bridged in female) - Walmart.com
AC WORKS 3-Prong 50A Dryer/Range Plug to 4-Prong Dryer Female Connector Adapter S10501430-018 - The Home Depot