12 Pin Military Vehicle to 7 Blade Civilian Trailer Adapter – Federal Military Parts (763) 310-9340
Reese Towpower Wiring Adapter, 7-way Round To 5-way and 4-way Flat in the Trailer Parts & Accessories department at Lowes.com
Amazon.com: OPT7 7 Pin to 4 Pin Trailer Adapter with Secure Tab, 7 Way Blade to 4 Way Flat Trailer Light Adapter, Connector for Trailer Tow Hitch and Redline LED Tailgate Light Bar : Automotive