diff --git a/usr.sbin/ppp/ppp.8 b/usr.sbin/ppp/ppp.8
index cbd81849ec9a..0b7c528daa03 100644
--- a/usr.sbin/ppp/ppp.8
+++ b/usr.sbin/ppp/ppp.8
@@ -3744,7 +3744,7 @@ All ISDN and serial device names are expected to begin with
 ISDN devices are usually called
 .Pa i4brbchX
 and serial devices are usually called
-.Pa cuaaX .
+.Pa cuaXX .
 .Pp
 If
 .Dq value
diff --git a/usr.sbin/ppp/ppp.8.m4 b/usr.sbin/ppp/ppp.8.m4
index cbd81849ec9a..0b7c528daa03 100644
--- a/usr.sbin/ppp/ppp.8.m4
+++ b/usr.sbin/ppp/ppp.8.m4
@@ -3744,7 +3744,7 @@ All ISDN and serial device names are expected to begin with
 ISDN devices are usually called
 .Pa i4brbchX
 and serial devices are usually called
-.Pa cuaaX .
+.Pa cuaXX .
 .Pp
 If
 .Dq value