diff --git a/ACadSharp/IO/DWG/DwgStreamReaders/DwgStreamReaderAC18.cs b/ACadSharp/IO/DWG/DwgStreamReaders/DwgStreamReaderAC18.cs
index 1d847dff..8c9feea5 100644
--- a/ACadSharp/IO/DWG/DwgStreamReaders/DwgStreamReaderAC18.cs
+++ b/ACadSharp/IO/DWG/DwgStreamReaders/DwgStreamReaderAC18.cs
@@ -89,7 +89,7 @@ public override Color ReadEnColor(out Transparency transparency, out bool flag)
 				else
 				{
 					//Color index: if no flags were set, the color is looked up by the color number (ACI color).
-					color = new Color((byte)(size & 0b111111111111));
+					color = new Color((short)(size & 0b111111111111));
 				}
 
 				//0x2000: color is followed by a transparency BL