The gnasher graph?

Could someone please tell me what the bottom numbers of the graph means of the gnasher lay out tht tc shows with the damage being on the left. What are the numbers at the bottom. I assume its feet but how many feet or yards is it. Example.

U will see 500,1000, 1500, 2000 , and 2500

(I dont know how to upload the graph but anyone tht has seen it should know what im talking about.)

Thanks

I believe its in unreal units.

And if its unreal units they are in centimeters.