Sub classing Class with implemented interface

I came back to the code and played with it some more.... Now I also see others have posted comments simular so hear is what I have

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Data.SqlClient;
using System.Security.Cryptography;
namespace ItemNameTest
{
    class Item : IEntityLoader
    {
        //Properties
        public string ItemCode { get; set; }
        public string ItemName { get; set; }
        public Item() //base constructor
        {
        }
        public Item(string SetItemName) //overloaded constructor
        {
            this.ItemName = SetItemName;
        }
        //Load object from Method implemented from the interface
        public void Load(SqlDataReader reader)
        {
            this.ItemCode = Convert.ToString(reader["Code"]);
            this.ItemCode = Convert.ToString(reader["Name"]);
        }
    }
    public interface IEntityLoader
    {
        void Load(SqlDataReader reader);
    }
    public class ItemDet : Item
    {
        private void TestMethod()
        {
            ItemName = "ItemDet Set";
            SqlDataReader reader = new SqlDataReader();
            Load(reader);
        }
    }
}