diff --git a/contenttype.go b/contenttype.go
index 676f971..13f244d 100755
--- a/contenttype.go
+++ b/contenttype.go
@@ -80,6 +80,7 @@ func SetContentTypeIfMedia(w http.ResponseWriter, r *http.Request) {
 	case ".eot":
 		v = "application/vnd.ms-fontobject"
 	case ".gz":
+		w.Header().Set("Content-Encoding", "gzip")
 		v = "application/gzip"
 	case ".gif":
 		v = "image/gif"