It's brand new and looks like a winters. I was told it wasn't but how do I identify it?

Mic the inner diameter of the tube. Winters and DMI have different bores. Check your measurement against the axles listed on their sites, or Conroy's bleeder list on their site. Will also.tell you what weight axle you have. For a sprint car Winters are 1.75, 1.875 and 2.055. DMI and Frankland are 1.9 and 2.0.