Insert Checkbox Selected Value into Database - asp.net-mvc

Question

I am trying to insert selected checkbox values to database. But I get an error
Unable to cast object of type 'System.Collections.Generic.List` to type 'System.String'
Please help. Thanks.
Model:
public class CheckboxModel
{
public int Id { get; set; }
public string Name { get; set; }
public bool Checked { get; set; }
}
public class MainModel
{
public List<CheckboxModel> CheckBoxes { get; set; }
}
HomeController:
// Get
public ActionResult Index()
{
MainModel model = new MainModel();
var list = new List<CheckboxModel>
{
new CheckboxModel{Id = 1, Name = "Male", Checked = false},
new CheckboxModel{Id = 2, Name = "Female", Checked = false},
};
model.CheckBoxes = list;
return View(model);
}
[HttpPost]
public ActionResult Create([Bind(Include = "Checkboxes")] MainModel model)
{
if (ModelState.IsValid)
{
db.MainModel.Add(model);
db.SaveChanges();
return RedirectToAction("Index");
}
return View(MainModel);
}
View:
#using (Html.BeginForm("Create", "Home", FormMethod.Post, new { enctype = "multipart/form-data" }))
{
#for (var i = 0; i < Model.Checkboxes.Count; i++)
{
<table>
<tr>
<td>
#Html.HiddenFor(m => Model.Checkboxes[i].Id)
#Html.HiddenFor(m => Model.Checkboxes[i].Name)
#Html.CheckBoxFor(m => Model.Checkboxes[i].Checked)
</td>
<td>
#Html.DisplayFor(m => Model.Checkboxes[i].Name)
</td>
</tr>
</table>
}