diff --git a/source/libtun/adapter.d b/source/libtun/adapter.d
index e1a2107..6838700 100644
--- a/source/libtun/adapter.d
+++ b/source/libtun/adapter.d
@@ -76,8 +76,8 @@ public final class TUNException : Exception
     }
 }
 
-public enum AdapterType
+public enum AdapterType : ushort
 {
-    TUN,
-    TAP
+    TUN = 1,
+    TAP = 0
 }
\ No newline at end of file