Woodhead 24052-0M Super-Safeway GFCI Flying Lead, Industrial Duty, Manual GFCI Reset, NEMA 5-20 Configuration, 12/3 SJEOOW Cord Type, 20A Current, 240V Voltage, 2ft Cord Length

I placed mismatched 20 amp plug and socket on this gfci and between 250 volt outlet and boat lift controller ( nema 6-20 & 14-30). I take this with me when I head for boat. Cannot forget to use GFCI as it is only way to connect, and when you leave dock, taking setup with you, no one can use your boat lift as outlet box mounted socket and boat lift controller plug do not match. GFCI function works well. Pricey, but you would be a fool to operate boat lift without one.