diff --git a/swugenerator/swu_sign.py b/swugenerator/swu_sign.py
index 437a0a5..53b6727 100644
--- a/swugenerator/swu_sign.py
+++ b/swugenerator/swu_sign.py
@@ -129,7 +129,7 @@ class SWUSignPKCS11(SWUSign):
         self.signcmd = [
             "pkcs11-tool",
             "-s",
-            "-m ",
+            "-m",
             "SHA256-RSA-PKCS",
             "-i",
             sw_desc_in,