diff --git a/scripts/wrapper-badblocks b/scripts/wrapper-badblocks
index 3de99ea..7f9a81a 100755
--- a/scripts/wrapper-badblocks
+++ b/scripts/wrapper-badblocks
@@ -74,7 +74,7 @@ else
 		done
 		smartctl -A -f brief /dev/$DISK \
 		| parse-smart-attr \
-		| sed 's/ERROR/$RES_ERROR/g' \
+		| sed "s/ERROR/$RES_ERROR/g" \
 			> $OUTPUT_DIR/disk/$SERIAL.smart.error
 	fi
 fi