Why does ASP.NET MVC Html.CheckBox output two INPUTs with the same name?

Question

Why in the world does the line:

<%= Html.CheckBox(\"ForSale\", Model.Product.ForSale)%> For Sale

result in the following HTML:

<

Answer 1

try

request.form["chkBoxes"].replace("false","").split(new char[] {','}, stringsplitoptions.removeemptyentries);