Product review (4 stars): Needs modifing
You need to cut a groove in the appliance cord end for polarity, no big issue for a rotary tool or something with a mild removal effect (razor blade?)
 I used a 3" cut off wheel tool(air powered) to make a small groove on the outside of the appliance cord end to somewhat match the end of the old cord and note the polarity,wide outlet tang to the same wire on the appliance end to match the groove you need to cut.