diff --git a/gifconv.bat b/gifconv.bat
index 9e9d964..1060697 100644
--- a/gifconv.bat
+++ b/gifconv.bat
@@ -120,7 +120,7 @@ MD "%WD%"
 :palettegen
 ECHO Generating Palette...
 IF DEFINED start_time (
-	IF DEFINED duration SET "trim=-ss %start_time% -t %duration%"
+	IF DEFINED duration SET "trim=-ss !start_time! -t !duration!"
 	IF NOT DEFINED duration (
 		ECHO Please input a duration
 		GOTO :EOF