diff --git a/usr/share/rear/backup/NETFS/default/500_make_backup.sh b/usr/share/rear/backup/NETFS/default/500_make_backup.sh
index 4726691..0c9c6eb 100644
--- a/usr/share/rear/backup/NETFS/default/500_make_backup.sh
+++ b/usr/share/rear/backup/NETFS/default/500_make_backup.sh
@@ -64,7 +64,7 @@ if [[ -n "$ISO_MAX_SIZE" ]]; then
     fi
     SPLIT_COMMAND="split -d -b ${ISO_MAX_SIZE}m - ${backuparchive}."
 else
-    SPLIT_COMMAND="dd of=$backuparchive"
+    SPLIT_COMMAND="dd of=$backuparchive bs=1M"
 fi
 
 LogPrint "Creating $BACKUP_PROG archive '$backuparchive'"