ViewBag.LocationID = new SelectList(db.LOCATIONS, "LocationID", "Name");
 ViewBag.SupplierID = new SelectList(db.SUPPLIERS, "SupplierID", "Name");

<div class="form-group">
        @Html.LabelFor(model => model.SupplierID, "Supplier:", htmlAttributes: new { @class = "control-label col-md-2" })
        <div class="col-md-10">
            @Html.DropDownList("SupplierID", null, htmlAttributes: new { @class = "form-control" })
            @Html.ValidationMessageFor(model => model.SupplierID, "", new { @class = "text-danger" })
        </div>
    </div>