diff --git a/websocket-sharp/Net/QueryStringCollection.cs b/websocket-sharp/Net/QueryStringCollection.cs
index 9d47e08d..564debdd 100644
--- a/websocket-sharp/Net/QueryStringCollection.cs
+++ b/websocket-sharp/Net/QueryStringCollection.cs
@@ -48,6 +48,19 @@ namespace WebSocketSharp.Net
 {
   internal sealed class QueryStringCollection : NameValueCollection
   {
+    #region Public Constructors
+
+    public QueryStringCollection ()
+    {
+    }
+
+    public QueryStringCollection (int capacity)
+      : base (capacity)
+    {
+    }
+
+    #endregion
+
     #region Public Methods
 
     public static QueryStringCollection Parse (string query)