diff --git a/usr/local/www/system_advanced_firewall.php b/usr/local/www/system_advanced_firewall.php
index 10b8799028..8430ac0444 100644
--- a/usr/local/www/system_advanced_firewall.php
+++ b/usr/local/www/system_advanced_firewall.php
@@ -427,6 +427,8 @@ function update_description(itemnum) {
 									<strong><?=gettext("Automatically create outbound NAT rules which assist inbound NAT rules that direct traffic back out to the same subnet it originated from.");?></strong>
 									<br/>
 									<?=gettext("Required for full functionality of the pure NAT mode of NAT Reflection for port forwards or NAT Reflection for 1:1 NAT.");?>
+									<br/><br/>
+									<?=gettext("Note: This only works for assigned interfaces.  Other interfaces require manually creating the outbound NAT rules that direct the reply packets back through the router.");?>
 								</td>
 							</tr>
 							<tr>