diff --git a/python/semanage/semanage-node.8 b/python/semanage/semanage-node.8
index e0b0e56c..a0098221 100644
--- a/python/semanage/semanage-node.8
+++ b/python/semanage/semanage-node.8
@@ -45,7 +45,7 @@ Extract customizable commands, for use within a transaction
 Remove all local customizations
 .TP
 .I   \-M NETMASK, \-\-netmask NETMASK
-Network Mask
+Network Mask, either in CIDR (/16) or address mask notation (255.255.0.0, ffff::)
 .TP
 .I   \-t TYPE, \-\-type TYPE
 SELinux type for the object