50 AMP 30 FT. Extesion Cord

[kartracer]

I need a 50 Amp 125/250 Volt 30 Foot extension cord. What size wire would I need and is it 3 or 4 wire. If I back into a slip cords I have are not long enough to reach deck box.

 

[TomandJeri]

Maybe a stupid question, but can't you just use a 25 ft 125/250V 50A marine shore power cord as an extension?

Cordset, 50A 125/250V, 25', Yellow | Marinco

Oh, and 6-gauge copper for 50A, with 4 conductors for 125/250V.