diff --git a/conf/bind_add_dkim_zone_master.conf.sample b/conf/bind_add_dkim_zone_master.conf.sample
index 4912610..8907d38 100644
--- a/conf/bind_add_dkim_zone_master.conf.sample
+++ b/conf/bind_add_dkim_zone_master.conf.sample
@@ -33,6 +33,7 @@
 # - ALLOW_TRANSFER_OPTION
 # -
 # - Example:
-# -    ALLOW_TRANSFER_OPTION="oopen"
+# -    ALLOW_TRANSFER_OPTION="oopen;"
+# -    ALLOW_TRANSFER_OPTION="83.223.90.93;"
 # -
 #ALLOW_TRANSFER_OPTION=""