This is an Aftermarket Boss 13 Pin Vehicle Side Repair End Female MSC04753. 

Used on RT3 Straight and V Blade with 13 Pin Wiring. 

Alternate Part Numbers: MSC04753, MSC4753, 1304745

For Plow Side Repair End See MSC4754. 

For Vehicle Side & Plow Side Repair Kit see MSC4753-54.