diff --git a/SabreTools.Models/Logiqx/GameBase.cs b/SabreTools.Models/Logiqx/GameBase.cs
index cdca3a6..990c0ef 100644
--- a/SabreTools.Models/Logiqx/GameBase.cs
+++ b/SabreTools.Models/Logiqx/GameBase.cs
@@ -111,5 +111,13 @@ namespace SabreTools.Models.Logiqx
         /// <remarks>MAME extension</remarks>
         [XmlElement("softwarelist")]
         public SoftwareList[]? SoftwareList { get; set; }
+
+        /// <remarks>RetroAchievements extension</remarks>
+        [XmlAttribute("url")]
+        public string? Url { get; set; }
+
+        /// <remarks>RetroAchievements extension</remarks>
+        [XmlAttribute("hash")]
+        public string? Hash { get; set; }
     }
 }
\ No newline at end of file
diff --git a/SabreTools.Models/Metadata/Machine.cs b/SabreTools.Models/Metadata/Machine.cs
index 805cc0b..8c48d04 100644
--- a/SabreTools.Models/Metadata/Machine.cs
+++ b/SabreTools.Models/Metadata/Machine.cs
@@ -113,6 +113,9 @@ namespace SabreTools.Models.Metadata
         /// <remarks>string</remarks>
         public const string GenMSXIDKey = "genmsxid";
 
+        /// <remarks>string</remarks>
+        public const string HashKey = "hash";
+
         /// <remarks>string</remarks>
         public const string HistoryKey = "history";
 
@@ -260,6 +263,9 @@ namespace SabreTools.Models.Metadata
         [NoFilter]
         public const string TruripKey = "trurip";
 
+        /// <remarks>string</remarks>
+        public const string UrlKey = "url";
+
         /// <remarks>Video[]</remarks>
         [NoFilter]
         public const string VideoKey = "video";