diff --git a/src/Windows/Perspex.Win32/Embedding/EmbeddedWindowImpl.cs b/src/Windows/Perspex.Win32/Embedding/EmbeddedWindowImpl.cs
index a4e6bec9e4..052e83a28f 100644
--- a/src/Windows/Perspex.Win32/Embedding/EmbeddedWindowImpl.cs
+++ b/src/Windows/Perspex.Win32/Embedding/EmbeddedWindowImpl.cs
@@ -19,10 +19,10 @@ namespace Perspex.Win32
                 atom,
                 null,
                 (int)UnmanagedMethods.WindowStyles.WS_CHILD,
-                UnmanagedMethods.CW_USEDEFAULT,
-                UnmanagedMethods.CW_USEDEFAULT,
-                UnmanagedMethods.CW_USEDEFAULT,
-                UnmanagedMethods.CW_USEDEFAULT,
+                0,
+                0,
+                640,
+                480,
                 WinFormsControl.Handle,
                 IntPtr.Zero,
                 IntPtr.Zero,