SPREAD is this.

The bookmaker says the final margin,for example,Port and Richmond,will be between 12 and 20 points.
If I think Port will win by more,I receive an amount equivalent to my stake for every point over the 20 points margin.
But.
I need to pay an amount equivalent to my stake for every point less than 12 points if the margin is less than 12.
If the margin is the spread (12-20) I lose my stake.
Could be scary!

Mo.