Have Cord 4 Prong other end Copper Red White & Black

Female White Ground X & why

Black X ? Red why ?

Once I make this I have an extension Correct

Need X & why correct as not marked on male end of cord. Thank You.

X and Y are stamped on cord connector bodies to assist in keeping wires connected the same, if you so desire.

Black and Red can go on either X or Y.

Conductors in cord is color coded.

Connect white to silver terminal, ground to green, and black and red to either X or Y.